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    Wyświetlanie 1-59 z 59
    Tytuł:
    Probability of Solar Flares Turn Out to Form a Coronal Mass Ejections Events Due to the Characterization of Solar Radio Burst Type II and III
    Autorzy:
    Hamidi, Z. S.
    Powiązania:
    https://bibliotekanauki.pl/articles/412360.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    solar flare
    Coronal Mass Ejection
    solar burst
    type II
    type III
    space Feather
    Opis:
    The solar flare and Coronal Mass Ejections (CMEs) are well known as one of the most massive eruptions which potentially create major disturbances in the interplanetary medium and initiate severe magnetic storms when they collide with the Earth‟s magnetosphere. However, how far the solar flare can contribute to the formation of the CMEs is still not easy to be understood. These phenomena are associated with II and III burst it also divided by sub-type of burst depending on the physical characteristics and different mechanisms. In this work, we used a Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy in Transportable Observatories (CALLISTO) system. The aim of the present study is to reveal dynamical properties of solar burst type II and III due to several mechanisms. Most of the cases of both solar radio bursts can be found in the range less that 400 MHz. Based on solar flare monitoring within 24 hours, the CMEs that has the potential to explode will dominantly be a class of M1 solar flare. Overall, the tendencies of SRBT III burst form the solar radio burst type III at 187 MHz to 449 MHz. Based on solar observations, it is evident that the explosive, short time-scale energy release during flares and the long term, gradual energy release expressed by CMEs can be reasonably understood only if both processes are taken as common and probably not independent signatures of a destabilization of pre-existing coronal magnetic field structures. The configurations of several active regions can be sourced regions of CMEs formation. The study of the formation, acceleration and propagation of CMEs requires advanced and powerful observational tools in different spectral ranges as many „stages‟ as possible between the photosphere of the Sun and magnetosphere of the Sun and magnetosphere of the Earth. In conclusion, this range is a current regime of solar radio bursts during CMEs events.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 16; 1-85
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Chronology of Formation of Solar Radio Burst Types III and V Associated with Solar Flare Phenomenon on 19th September 2011
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/411656.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    solar radio burst
    solar flare
    type III
    type V
    CALLISTO
    Opis:
    The formation of two different solar bursts, type III and V in one solar flare event is presented. Both bursts are found on 19th September 2011 associated with C-class flares on active region 1295. From the observation, we believed that the mechanism of evolution the bursts play an important role in the event. It is found that type V burst appeared in five minutes after type III. There are a few active regions on the solar disk but most are magnetically simple and have remained rather quiet. An interpretation of this new result depends critically on the number of sunspots and the role of active region 1295. Sunspot number is increased up to 144 with seven sunspots can be observed. During that event, the speed of solar wind exceeds 433.8 km/second with 2.0 g/cm3 density of protons in the solar corona. Currently, radio flux is also high up to 150 SFU. The solar flare type C6 is continuously being observed in the X-ray region for 24 hours since 1541 UT and a maximum C1 is detected on 1847 UT. Although the sources of both bursts are same, the direction and ejection explode differ.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 5; 32-42
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Investigation of Radio Frequency Interference (RFI) Profile and Determination of Potential Astronomical Radio Sources
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/411988.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Radio Frequency Interference (RFI)
    radio astronomy
    RFI sources
    Opis:
    In this article, we have recognized a Radio Frequency Interference (RFI) sources that can potentially affect for radio astronomical observation. The main objective of this surveying is to test and qualify the potential of radio astronomical sources that can be observed in Malaysia generally. Analysis process focuses on the high sources that contribute the pollution and the significant region that can be considered for astronomical purpose beginning 1-2000 MHz. It was found that 13 individual sources contribute as a noise and mostly are telecommunication and radio navigation applications. We then compared of the RFI profiles based on three different periods in order to observe the variety of the signals. The main regions that still excellent to do an observation are: 13.36 -13.41 MHz (solar), (25.55-25.67) MHz (Jupiter) and (37.50-38.25) MHz (Continuum) respectively. This work is also an initiative of the International Space Weather Initiative (ISWI) project where Malaysia is one of the countries that involve in e-CALLISTO (Compound Astronomical Low Cost Low Frequency Transportable Observatory) network project. Some suggestions are recommended in order to improve the quality of the radio frequency profile.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 5; 43-49
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Detailed Investigation of a Moving Solar Burst Type IV Radio Emission in on Broadband Frequency
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/412146.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Solar radio emission
    solar burst type IV
    e-CALLISTO
    solar flare
    Active Region 1429
    Opis:
    The moving type IV burst component of the solar radio region from 260-380 MHz observed using the CALLISTO spectrometer is discussed in detail. We used the Compound Astronomical Low Cost Low Frequency Spectrometer Transportable Observatory (CALLISTO) system connected to the Log Periodic Dipole Antenna (LPDA) at the National Space Centre, Selangor located (3.0833333°N 101.5333333°E) on 22nd February 2012. It is found that a strong burst that caused by extraordinary solar flares are due to magnetic reconnection effect potentially induced in the near-Earth magneto tail. From our observation the indication of signal potentially drives Coronal Mass Ejections (CMEs). We also compare our results with the Geostationary Operational Environmental Satellites (GOES) data. From our analysis, one possible reason behind the formation of this very complex long duration of this loop is the magnetic reconnection and disruption of the loops which is observed during flare maximum. The Active Region, AR 1429 active region was a site of several intense in several days. From the results, it showed that the burst is formed from the explosion of M-class solar flare which can be observed at 412UT. As a conclusion, a good agreement was reached and we believe that Sun’s activities are more active to pursuit the solar maximum cycle.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 7; 30-36
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Determination of Flux Density of the Solar Radio Burst Event by Using Log Periodic Dipole Antenna (LPDA)
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/412450.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    sun
    CALLISTO
    Log Periodic Dipole Antenna (LPDA)
    power flux density
    solar radio burst
    Opis:
    In this article, an evaluation of the flux density of the solar radio burst is presented. A rod aluminium’s type as a conductor with nineteenth (19) elements of different sizes is being prepared to construct a log periodic dipole antenna (LPDA) from 45-870 MHz. The performance was carried out at the National Space Agency (PAN), Sg. Lang, Banting Selangor by connecting to the Compound Low Cost Low Frequency Spectroscopy Transportable Observatory (CALLISTO) spectrometer. The input impedance, R0 = 50 ohm is chosen for this LPDA antenna. From the analysis, the gain of the antenna is 9.3 dB. This antenna potentially captures a signal that covers about 0.08 m2 area of the Sun.The temperature of the burst that detected at the feedpoint of the antenna is 32 K. However, the signal becomes decrease to 28.75 K while by CALLISTO spectrometer as a receiver. It was also found that the isotropic source spectral power is 1576 W/Hz. Since the burst level above the background sky is 0.41 dB , the flux density of the burst is 5.5 x 10-21 W/m2/Hz. Based on the results, we conclude that this antenna is suitable for to observe the Sun activities at low frequency region.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 7; 21-29
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Enormous Eruption of 2.2 X-class Solar Flares on 10th June 2014
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/411754.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    sun
    X-ray region
    solar flare
    active region
    Opis:
    The observational of active region emission of the Sun contain an critical answer of the time-dependence of the underlying heating mechanism. In this case, we investigate an X2.2 solar flare from a new Active Region AR2087 on the southeast limb of the Sun. The solar flare peaked in the X-rays is around 11:42 UT. It was found that the snapshot of this event from the Solar Dynamics Observatory (SDO) channel with the GOES X-ray plot overlayed. The flare is very bright causes by a diffraction pattern. We explore a parameter space of heating and coronal loop properties. Based on the wavelength, it shows plasma around 6 million Kelvin. At the same time, data from the NOAA issued an R3 level radio blackout, which is centered on Earth where the Sun is currently overhead at the North Africa region. This temporary blackout is caused by the heating of the upper atmosphere from the flare. The blackout level is now at an R1 and this will soon pass. Other than the temporary radio blackout for high frequencies centered over Africa this event will not have a direct impact on us. Until now, we await more data concerning a possible Coronal Mass Ejections (CMEs) but anything would more than likely not head directly towards Earth. An active region AR2087 just let out an X1.5 flare peaking at 12:52 UT. This shows plasmas with temperatures up to about 10 Million Kelvin. This event is considered one of the massive eruption of the Sun this year.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 17, 3; 249-257
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Nonlinear Behavior of the Radio Frequency Interference (RFI) Sources at Faculty of Applied Sciences, MARA University of Technology
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/412047.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Radio Frequency Interference (RFI)
    RFI sources
    solar radio burst
    CALLISTO
    Opis:
    In this article, we describe and compare several sources of the nonlinear of Radio Frequency Interference (RFI) based on classification methods. It is very important to characterize and understand the nature of interference in as much of the candidate spectrum as possible. Preliminary analysis has been done in 2011. As data sizes of observations grow with new and improved solar monitoring system, the need for completely automated, robust methods for RFI mitigation is highlighted. The current status of RFI noise level is being compared at two different sites (i) indoor and (ii) outdoor. The main objective is to evaluate and find the best range of low frequency in MHz for the solar monitoring purpose. Our findings are consistent with those of previous studies. There is not much different in terms of the sources of RFI. However, the level of RFI is become increase. Based on the results, it was found that the distribution of RFI sources in indoor site is in the range from -(80-105) dBm. A strong and moderate RFI can be identified in the range of -100 dBm. The dominant sources in this region are due to the fixed mobile signal with 10 points of this signal from 1-2000 MHz. If we compare with outdoor site, the distribution of RFI sources in indoor site is in the range from -(75-105) dBm. It means that the signal of noise is larger compared with indoor site. While new sources strive to remain the increasing of RFI signal levels, numerous factors interact to influence the pattern of this noise. Reporting to the authoritative body should be made to make sure the allocation of the solar monitoring frequency region was not used by other applications. This work is a current scenario of the nonlinear RFI level at our site.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 15; 39-47
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The Propagation of An Impulsive Coronal Mass Ejections (CMEs) due to the High Solar Flares and Moreton Waves
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/412288.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    sun
    solar eclipse
    solar radio
    burst
    type III
    e-CALLISTO
    Opis:
    This paper provides a short review of some of the basic concepts related to the origin of Coronal Mass Ejections (CMEs). The numerous ideas which have been put forward to elucidate the initiation of CMEs are categorized in terms of whether this event is a gradual CME or impulsive CME. In this case, an earth-directed Coronal Mass Ejection (CME) was observed on April 2, 2014 by the Large Angle Spectrometric Coronagraph (LASCO) C2. This recent observations obtained a large impulsive CMEs. The CME, originating from the active region AR2027. The speed of CMEs is 1600 kms-1. A halo CME, a bright expanding ring at the North-West region is exploded beginning at about 14:36 UT, and the process of departing, expansion and propagation are highlighted. We discuss the correspondence of this event with the structure of the CME in the LASCO data. It is believed that the high solar flare and a Moreton waves initiate this kind of CMEs.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 14, 1; 118-126
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The Mechanism of Signal Processing of Solar Radio Burst Data in E-CALLISTO Network (Malaysia)
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/412533.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Space weather
    CALLSITO system
    ISWI (International Space Weather Initiative)
    sun
    solar radio burst
    solar activity
    signal processing
    e-network
    Opis:
    Solar space weather events like Coronal Mass Ejections and solar flares are usually accompanied by solar radio bursts, which can be used for a low-cost real-time space weather monitoring. In order to make a standard system, a CALLISTO (Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy in Transportable Observatory) spectrometers, designed and built by electronics engineer Christian Monstein of the Institute for Astronomy of the Swiss Federal Institute of Technology Zurich (ETH Zurich) have been already developed all over the world since 2005 to monitor the solar activities such as solar flare and Coronal Mass Ejections (CMEs). Up to date, there are 25 sites that used the same system in order to monitor the Sun within 24 hours. This outstanding project also is a part of the United Nations together with NASA initiated the International Heliophysical Year IHY2007 to support developing countries participating in ‘Western Science’. Beginning February 2012, Malaysia has also participated in this project. The goals of this work is to highlight how does the signal processing of solar radio burst data transfer from a site of National Space Centre Banting Selangor directly to the Institute of Astrophysics Switzerland. Solar activities in the low region, focusing from 150 MHz to 400 MHz is observed daily beginning from 00.30UT 12.30 UT. Here, we highlighted how does the signal processing work in order to make sure that the operation is in the best condition. Although the solar activities have experienced rapid growth recently, high-level management of CALLISTO system has remained successfully manage the storage of data. It is also not easy to maintain the future data seems the number of sites are also growing from time to time. In this work, we highlighted the potential role of Malaysia as one of the candidate site that possible gives a good data and focusing on a few aspects such as optimization, and performance evaluation data and visualization.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 15; 30-38
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Observations of Different Type of Bursts Associated with M 6.3 Solar Flares
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/412558.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    sun
    low frequency
    solar radio
    burst
    type III
    type U
    e-CALLISTO
    Opis:
    Variation of solar bursts due to solar flares such as type an isolated type III , a complex type III, U is being highlighted. These bursts occurred on 9th March 2012 at the National Space Centre, Sg. Lang, Selangor, Malaysia Here, we study a unique case with a combination of two types burst associated with solar flare and CMEs. Our observation is focused on the low frequency region starting from 150 MHz till 400 MHz. We found that a solar flare type solar flare type M 6.3 which occurred in active region AR 1429 starting from 3:32 UT and ending at 05:00 UT. The flare has been confirmed to be the largest flare since 2005. Some physical parameters will be measured. We then compared our results with X-ray data from NOAA Space Weather Prediction Centre (SWPC).
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 4; 29-36
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    First Light Detection of A Single Solar Radio Burst Type III Due To Solar Flare Event
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/411677.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Solar flare
    low frequency
    radio wavelength
    solar burst
    type III
    CALLISTO
    Opis:
    The eruption mechanism of solar flares and type III are currently an extremely active area of research, especially during the solar cycle is towards maximum. In this case, the total energy of solar burst type III is of the order of solar flare with the explosion of the energy can up to 1015 ergs. The solar flare event is one of the most spectacular explosions that still be on-going study in the solar physics world. This event occurred at 2:000 UT on 15th April 2012 is due to the explosion of the magnetic energy in from the chromosphere and converted into the heating, mass motion and particle acceleration which can be detected by solar radio burst type III. In this work, we will highlight our first light detection of very tiny solar radio burst type III, which has been observed at the National Space Centre, Banting, Selangor detected by the Compound Low Cost Low Frequency Transportable Observatories (CALLISTO) system at 5:53:23. The region of the data is from 150 − 400 MHz in radio region. This burst is drifted from 150 MHz till 260 MHz. It represents a total energy of 6.2035 × 10-7 eV − 1.0753 × 10-6 eV. This fast drift burst is a continuity of the acceleration of the particles which is intermittent, and can be observed since the explosion of the solar flare. Although the burst is very tiny, it is still significant because this burst is the first detection of a single type III burst from our site. Still, the acceleration of the particles can be detected from Earth in the radio region within 3 hours period of observation at the post stage of solar flare.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 11, 1; 51-58
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Scenario of Solar Radio Burst Type III During Solar Eclipse on 14th November 2012
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/411752.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    sun
    solar eclipse
    solar radio
    burst
    type III
    e-CALLISTO
    Opis:
    A compact solar flare was observed during a total solar eclipse event on 13-14 November 2012. This phenomenon is beginning in local time on November 14 west of the date line over northern Australia, and ended in local time on November 13 east of the date line near the west coast of South America. During the eclipse, the highest magnitude was 1.0500, occurring only 12 hours before perigee, with the maximum eclipse totality lasting just over four minutes. Considering the observational facts, the solar radio burst type III can be detected from the National Space Centre Malaysia by the Compound Low Cost Low Frequency Transportable Observatory (CALLISTO) system from 00:00 UT –1:30 UT. The group and individual solar burst type III can be detected in the region of 150-400 MHz. However, the eclipse cannot be observed from our site. From the observation, it was found that the eruption in the active region is becoming more active with a tens of groups solar radio burst type III can be observed. It continuing bursting within the first one hour. The sunspot number exceeds to 108 and solar wind speed 454.9 km/sec. Still the Sun remains active and we need to consider other processes to explain in detailed the injection, energy loss and the mechanism of the acceleration of the particles.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 13, 2; 135-143
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The Different Between the Temperature of the Solar Burst at the Feed Point of the Log Periodic Dipole Antenna (LPDA) and the CALLISTO Spectrometer
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/411932.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    CALLISTO
    Log Periodic Dipole Antenna
    LPDA
    temperature
    solar radio burst
    Opis:
    The article attempts to analyze and compare the temperature of solar radio burst at the (i) feed point and antenna and (ii) at the receiver (CALLISTO spectrometer). The analysis is very important to evaluate the performance for a better observation of solar radio burst. We start our project by developing this antenna with 19 elements of different sizes covers from 45 − 870 MHz. We choose the National Space Agency (PAN), Sg. Lang, Banting, Selangor, Malaysia as our site seems this site has a very minimum of Radio Frequency Interference (RFI). The antenna, then connects to the low noise amplifier and the CALLISTO spectrometer as one complete system. Based on the results, it was found that the temperature of the at the feed point of the antenna and receiver is different up to 3.25 K. The average level burst level above background sky is about 0.41dB. It was found that the power of solar burst at the feed point of the antenna is equivalent to 2.6 x 10-18 W, but decreases to 2.3 x 10-18 W when detected by the CALLISTO spectrometer. These results show a better understanding of how does the system operate in terms of the process of analysis of the temperature of solar radio burst.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 11, 2; 167-176
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Occurrences Rate of Type II and III Solar Radio Bursts at Low Frequency Radio Region 45 − 870 MHz
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/412187.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    CALLISTO
    low frequency
    solar burst
    type II
    type III
    solar flare
    Coronal Mass Ejections
    CMEs
    Opis:
    Observations of type II and III solar bursts indicate that while type III bursts may appear at any altitude, from the very low corona into interplanetary space, type II solar bursts do not act the same way. This work focuses on recent observations in the radio region on the low frequency region from 45 MHz to 870 MHz. Our analysis employed the accuracy of the daily solar burst measurements of e-CALLISTO network. It was found that solar burst type II explode quite minimum with 1-2 events from 2006 - 2010. However, the data 2011 for solar burst type II increases drastically with 16 events has been recorded. The occurrences of Coronal Mass Ejections (CMEs) events are also increasing up to four times in 2011. Most of the both events can be observed in the range of 150 MHz till 500 MHz. Overall, we can say that the range of photon energy for solar burst type III is between 7.737 x 10-7 eV to 1.569 x 10-6 eV. In the case of solar burst type II, the distribution of energy is much smaller with 1.596 x 10-6 eV to 6.906 x 10-6 eV. Detailed investigation of solar burst will concern the 2011 data seem to show a significant trend for both types. We showed that the increasing of both solar burst events via years implies directing an increasing of solar activities including sunspot number, solar flare and Coronal Mass Ejections (CMEs) events. It is expected that both types will increase gradually in the beginning of 2014.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 18; 103-112
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    An Observation of an Inverted Type U Solar Burst Due to AR1429 Active Region
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/412209.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    CALLISTO
    low frequency
    solar burst
    type U
    Radio Frequency Interference (RFI)
    Opis:
    A detailed investigation of an inverted type U solar burst in meter region and their associated the solar flare and Coronal Mass Ejections (CMEs) has been reported. Solar type U burst has been observed at the National Space Centre, Banting, Selangor detected by the Compound Low Cost Low Frequency Transportable Observatories (CALLISTO) system in the 150 MHz till 400 MHz at the low frequency band. An inverted U type is occurring on 9th March 2012 between 4:00 UT to 4:15 UT within 1 minute (4:12 − 4:13) UT. From the dynamic spectra of CALLISTO, we have identified metric type U burst with maximum emission near the frequency 385MHz. In specific, the continuum type III burst will soon structure this burst due to our observations. Other types such as type II and IV are only appearing only after type U burst is ejected and appear at the same point of the solar flare event. Since the U burst activity coincides with the peak of the hard X-ray flare at 4:12UT in AR1429, we classified that the event is associated with the injection of the high energetic particles. In conclusion, it is confirmed that an inverted type U burst is initiated after a complex and a group solar radio burst type III.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 10; 81-90
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Characterization of Selected Solar Radio Bursts Based on Solar Activity Detected by e- CALLISTO (Malaysia)
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/412630.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    sun
    low frequency
    solar radio
    burst
    type II
    type III
    type IV
    type V
    type U
    e-CALLISTO
    Opis:
    One of the main reasons to study more about the dynamics of solar radio bursts is because solar these bursts can interfere with the Global Positioning System (GPS) and communications systems. More importantly, these bursts are a key to understand the space weather condition. Recent work on the interpretation of the low frequency region of a main solar burst is discussed. Continuum radio bursts are often related to the solar activities such as an indication of the formation of sunspot, impulsive phase of solar flares and Coronal Mass Ejections (CMEs) and their frequencies correspond to the densities supposed to exist in the primary energy release volume. Specifically, solar burst in low frequency play an important role in interpretation of Sun activities. In this work, we have selected few solar bursts that successfully detected by our station at the National Space Centre, Banting Selangor. Our objective is to correlate the solar burst with Sun activities by looking at the main sources that responsibility with the trigger of solar burst. It is found that type II burst is dominant with Coronal Mass Ejections (CMEs), type III burst associated with solar flare, IV burst with the formation of active region and type U burst high solar flare. We believed that this work is a good start to monitor Sun’s activities in Malaysia as equatorial country.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 13, 2; 144-159
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Evaluation of Spectral Overview and Radio Frequency Interference (RFI) Sources at Four Different Sites in CALLISTO Network at the Narrow Band Solar Monitoring Region
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/412644.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    CALLISTO
    Radio Frequency Interference (RFI)
    RFI sources
    solar radio burst
    Opis:
    Continuous observation of solar radio burst in CALLISTO network was started since 2002 with Blein Switzerland is the first site that launched the system. Since then, there are more than 35 sites around the world that monitor the Sun activity within 24 hours until 2014. However, there is an issue of Radio Frequency Interference (RFI) that need to be considered. This noise is a major obstacle when performing observation with CALLISTO system. We selected 4 sites as preliminary analysis to analyze in detailed at a specific frequency which is very important in solar burst monitoring. The selected sites are (i) Blein, Switzerland (ii) Mauritius (iii) KASI Korea and (iv) ANGKASA, Malaysia. The regime narrow band that we focused are from (i) 72 – 75 MHz (ii) band 145 – 153 MHz (iii) 240 – 250 MHz (iv) 320 – 330 MHz (v) 406 – 410 MHz. The results of the sources of the RFI also will be highlighted. This work is was part of a larger study which focuses on a specific region that can be used for detailed investigation of solar burst. This issue of Radio Frequency Interference (RFI) needs a dialogue and interactions between different actors and networks.It is hoped that the analysis will help the solar physicist to choose a better data.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 11, 2; 135-145
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Understanding climate changes in Malaysia through space weather study
    Autorzy:
    Hamidi, Z.S.
    Shariff, N.N.M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/11399.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    climate change
    Malaysia
    weather
    Sun
    solar activity
    Earth
    interaction
    Opis:
    Space weather has a close connection with the interaction of the Earth and the Sun. As equatorial country, the characteristic features of the climate of Malaysia are uniform temperature, very high humidity and copious rainfall. Malaysia has an average of temperature of 26.7 °C per year. Therefore, it is suitable to monitor the Sun. In the following work, we will emphasize the development of Sun monitoring in Malaysia. The number of observatories are increasing. A dedicated work to understand the Sun activity in radio region is a part of an initiative of the United Nations together with NASA in order to support developing countries participating in „Western Science‟ research. Realizing how important for us to monitor the space weather, therefore, we have been utilizing the new radio spectrometer, CALLISTO (Compound Low Cost Low Frequency Transportable Observatories) spectrometer. Malaysia is one of the earliest country from South- East Asia (ASEAN) that involve this research. One of the advantages to start the solar monitoring in Malaysia is because our strategic location as equator country that makes possible to observing a Sun for 12 hours daily throughout a year. We strongly believe that Malaysia as one of contributor of solar activity data through E-CALLISTO network. This is a very good start for developing a space weather in Malaysia. With the implementation of CALLISTO systems and development of solar monitoring network, a new wavelength regime is becoming available for solar radio astronomy. Overall, this article presents an overview of space weather in Malaysia. With the present level of the international collaboration, it is believed that the potential involvement of local and international scientist in space weather will increase.
    Źródło:
    International Letters of Natural Sciences; 2014, 08, 1
    2300-9675
    Pojawia się w:
    International Letters of Natural Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Correlation between Radio Flux (10.7 cm) and Sunspot Number Based on Statistical Properties
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/1189949.pdf
    Data publikacji:
    2016
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Sun
    solar burst
    radio region
    solar flare
    Coronal Mass Ejections (CMEs)
    Opis:
    Statistical properties of solar radio burst radio type II and III of this work will be highlighted. One of the best advantages of using the radio method is that it allows high quality images within an arc second resolution and different frequencies actually cover different layers of the solar atmosphere. Statistical studies of both bursts are required to obtain such observational constraints with sufficient statistical confidence. In the first part, the trend of both bursts from 2006-2011 is examined. We need to consider a few parameters such as a burst duration, drift rate, energy of the photon, and the structure of the burst. From (0.0 0.5) MHz/Sec, the data represent the highest slope with m = 1290.1685 km/MHz in average. In the range of (4.0 7.0) MHz/Sec, the range of CMEs velocity is less than 500km/Sec. The lowest CMEs velocity that can be observed is ~137 km/Sec. The relationship between both parameters is F10.7cm = 0.4568R + 73.8655. This work presents the first step toward an analytical model of statistics of solar radio burst information of average events as something crucial to the acceleration mechanism.
    Źródło:
    World Scientific News; 2016, 52; 70-80
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The Development of Solar Astronomy In Malaysia
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/411541.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    sun
    radio emission
    solar radio burst
    Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy in Transportable Observatories
    CALLISTO
    solar flares
    Coronal Mass Ejections
    CMEs
    space Feather
    Opis:
    Monitoring the Sun reveals a variety of fascinating and complex physical phenomena which are being studied mainly by analyzing its emission. Solar activity has an impact with space weather. The characteristic features of the climate of Malaysia are uniform temperature, very high humidity and copious rainfall. It has an average of temperature of 26.7 ºC. Therefore, it is suitable to monitor the Sun. In following work, we will emphasize the development of solar astronomy in Malaysia. The ground based observation (i) optical and (ii) radio are the main region that we focused on. Optical observation has started earlier comparing with radio observation. In optical region it covers from 400 –700 nm while in radio region, we focus from 45 MHz to 870 MHz. The number of observatories is increasing. A dedicated work to understand the Sun activity in radio region is a part of an initiative of the United Nations together with NASA in order to support developing countries participating in „Western Science‟ research. Realize how important for us to keep doing a research about the solar bursts, by using the new radio spectrometer, CALLISTO (Compound Low Cost Low Frequency Transportable Observatories) spectrometer. Malaysia is one of the earliest country from South-East Asia (ASEAN) that involve this research. One of the advantages to start the solar monitoring in Malaysia is because our strategic location as equator country that makes possible to observing a Sun for 12 hours daily throughout a year. We strongly believe that Malaysia as one of contributor of solar activity data through E-CALLISTO network. This is a very good start for developing a radio astronomy in Malaysia. With the implementation of 45 MHz -870 MHz CALLISTO systems and development of solar burst monitoring network, a new wavelength regime is becoming available for solar radio astronomy. Overall, this article presents an overview of optical and radio astronomy in Malaysia. With the present level of the international collaboration, it is believed that the potential involvement of local and international scientist in solar astrophysics will increase.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 19, 1; 46-55
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Fundamental and Second Harmonic Bands of Solar Radio Burst Type II Caused by X1.8 - Class Solar Flares
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/411652.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    solar physics
    radio burst
    type II
    Zeeman Effect
    solar flare
    CALLISTO
    Opis:
    An extreme 2012 October 23 solar flare event marked on the onset of the CALLISTO data, being one of the highest solar flare event that successfully detected. The formation of harmonic solar burst type II in meter region and their associated with X1.8-class solar flares has been reported. This burst has been observed at the National Space Centre, Banting, detected by the Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy and Transportable Observatory (CALLISTO) system in the range of 150-400 MHz in the low frequency band. It occurred between 3.17:45 UT to 3.19:00 UT within 1 minute 15 seconds. The Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy and Transportable Observatory CALLISTO spectrometer is a solar dedicated spectrometer system that has been installed all over the world to monitor the Sun activity in 24 hours. The growth of this burst is often accompanied by abundance enhancement of particles which may take the form of multiple independent drifting bands or other forms of fine structure. Due to the results, the drift rate of this burst is 2.116 MHz s–1, which is considered as a slow drift rate. These drifting bands are approximately having a frequency ratio 2:1. This burst is a particular interest, though of sporadic and infrequent occurrence. The splitting is due to the effect of magnetic splitting, analogous to the Zeeman Effect. This is one of the examples which the type II burst is not always associated with CMEs event. The combination of radio and x-ray region give a complete view of the solar flare eruption from e active region AR1598. Both different electromagnetic spectrum shows the exact time. Other interesting results is that this type II burst is not associated with CMEs as usual, but due to the very high solar flare event with a fundamental form at more than 100 MHz. An extension of the present work will be a detailed study of the possible triggering and the driving mechanism of solar flare explosion.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 14, 2; 208-217
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Disturbances of Solar Eruption From Active Region AR1613
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/411713.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    solar radio emission
    solar burst type III
    e-CALLISTO
    solar flare
    Active Region AR1613
    Opis:
    The paper describes an investigation of the solar radio bursts of spectral type III due to disturbances of the active region AR 1613. A solar flare occurred on 2012 November 15, between 2:00 UT to 3:30 UT. The sequence images from a burst from our site revealed that although the solar flare is considered moderate, it is still possible to obtain the solar burst type III in a single and group forms within one and half hour. It can easily produce misleading results in terms of non-thermal electron density and magnetic field strength. The burst is originated in the same active region of the solar corona. The C-6 level enhancement was detected in GOES 1.8 a soft X-ray. Based on the results, we suggest that radio wave source motion manifests the displacement of particle sites caused by plasma eruptions. Time variability in the emission may due to the changes in the electron density. The group and individual solar burst type III can be related to the distance travelled before an electron beam becomes unstable to Langmuir waves. In conclusion, the interactions non-thermal electron and magnetic trapping can influence the transporting of electrons and this is still a subject of interest of intense investigation.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 13, 1; 77-87
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Type II Solar Radio Burst with a Split and Herring − Bones During a Minimum Solar Activity
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/411839.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    sun
    low frequency
    solar radio
    burst
    type II
    e-CALLISTO
    Opis:
    A preliminary correlation study of the herring − bone type II with a type III solar burst of has been made. On the basis of this study and in combination with the observation in radio emission, an interpretation of the mechanism of the occurrence of this event has been proposed. The type II solar radio burst with a split and herring bone is occurring at the same time from 36 MHz till 50 MHz. We have noted that an individual type III burst also can be observed at 13:23 UT from 45-50 MHz. During that day, a stream of solar wind from a coronal hole on the Sun has disturbing Earth's magnetosphere creating a minor geomagnetic storm, G1 on the NOAA scale of G1-G5. In this case, the solar flare is not very high, but CME is responsible to form a solar radio burst type II. Overall, based on seven days observation beginning from 25th March 2013, the solar activity is considered as very low. The highest solar flare can be observed within 7 days is only a class of B8 flare. There was no CMEs event that directed to the Earth is detected. The geomagnetic field activities are also at minimum level. Although the solar flare event is at a lower stage, it is still possible to form the solar radio burst type II which is associated with CME event. From the selected event, although theoretically solar radio burst type II is associated with CMEs, there is no compelling solar radio burst type II without a flare. The only difference is the dynamic structure and the intensity and speed of both phenomena (solar flares and CMEs) which depend on the active region. Nevertheless, understanding how energy is released in solar flares is one of the central questions in astrophysics. This solar radio burst type II formation is the first event that successfully detected by e-CALLISTO network in 2013.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 13, 2; 104-111
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Statistical Study of Nine Months Distribution of Solar Flares
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/412246.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    sun
    solar eclipse
    solar radio
    burst
    type III
    e-CALLISTO
    Opis:
    Solar flare is one of the solar activities that take place in the outermost layer of the corona. Solar flares can heat the material to several million degrees in just a few minutes and at the same time they release the numerous amount of energy. It is believed that a change of magnetic field lines potentially creates the solar flares. The objectives of the study are to identify and compare the types of solar flares (in X-Ray) region and to improve understanding of solar flares. Data are taken from the NOAA website, from the United States Department of Commerce, NOAA, Space Weather Prediction Center (SPWC). Solar radio flux readings were merged together with the three classes and a total of nine graphs were plotted. In illustrating the relationship of solar radio flux and solar flares, it can be explained by studying the range values of flux corresponding to flares values. From this case study, it was found that the minimum value of solar radio flux in order for the flares to occur is equivalent 68 x 10-22Wm-2Hz-1. Thus, whenever the values of solar radio flux are high, there should be a higher number of flares produced by the sun. The overall range of solar radio flux recorded in this study ranging from 68 x 10-22 Wm-2Hz-1 to 96 x 10-22 Wm-2Hz-1. Observing and collecting data from the Sun and develop our very own new prediction methods will leads the accuracy of the prediction of the behavior of the Sun more precisely.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 14, 1; 1-11
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Comparison of the Radio Frequency Interference (RFI) in the Region of Solar Burst Type III Data At Selected CALLISTO Network
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/412319.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    CALLISTO
    low frequency
    solar burst type III
    Radio Frequency Interference (RFI)
    Opis:
    Compact Astronomical Low-frequency, Low-cost Instrument for Spectroscopy in Transportable Observatories (CALLISTO) is a global network of spectrometer system with the purpose to observe the Sun’s activities. There are 25 stations that are used for this purpose. Radio Frequency Interference (RFI) is a major obstacle when performing observation with CALLISTO. We have confirmed at least 2 stations out of 10 stations with a complete overview spectral (OVS) made available to us showed clear detection of these consistent types of RFI for each specific region. In Malaysia, these RFI are also clearly detected. The major RFI affecting CALLISTO within radio astronomical windows below 1 GHz are local electronic system specifically radio navigation (at 73.1 MHz and 75.2 MHz), broadcasting (at (i) 151 MHz, (ii) 151.8 MHz and 152 MHz), aeronautical navigation (at (i) 245.5 MHz, (ii) 248.7 MHz and (iii) 249 MHz and fixed mobile at (i) 605 MHz, (ii) 608.3 MHz, (iii) 612.2 MHz, (iv) 613.3 MHz). It is obviously showed that all sites within this region are free from interference at 320-330 MHz and is the best specific region to be considered for solar burst monitoring. We also investigate the effect of RFI on detection of solar burst. We have considered type III solar bursts on 9th March 2012 in order to measure the percentage of RFI level during the solar burst. The RFI level is as low as 6.512 % to 80.769 % above solar burst detection.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 10; 38-45
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Radio Observation of Coronal Mass Ejections (CMEs) Due to Flare Related Phenomenon on 7th March 2012
    Autorzy:
    Hamidi, Z. S.
    Monstein, C.
    Shariff, N. N. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/412379.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Radio burst
    solar flare
    Coronal Mass Ejections (CMEs)
    e-CALLISTO
    Active Region 1429
    Opis:
    On March 7th, 2012, an active region AR1429 has unleashed 2 major X-class solar flares. This flare is accompanied by a Coronal Mass Ejections (CMEs) event. A pair of unusually large solar flares early March 7, 2012 generated a Coronal Mass Ejection that was expected to reach Earth around midday March 8. In this case we focused on the second explosion of solar flare. It is found that the indication of signal potentially drives Coronal Mass Ejections (CMEs). There are a few types solar burst that can be observed, which is (i) an individual type III (ii) a complex type III (iii) subtype an H type II solar burst and (iv) type IV solar burst. The duration of solar burst is start from 1:02 UT to 2:00 UT. We also compare our results with the Geostationary Operational Environmental Satellites (GOES) data. Overall, one hour duration with a strong intensity burst are exploded strongly within the period. The fast drift type III burst has continued until 1:28 UT is associated with the large X 5.4 -class solar flares at 1:25:05 UT. It is undeniable that solar flare plays an important role in the Sun-Earth connection due to sudden changes of strong magnetic fields in the Sun’s corona. From our analysis, one possible reason behind the formation of this very complex, long duration of this loop is the magnetic reconnection and disruption of the loops which is observed during flare maximum. Until now, there has been an increasing interest in the space weather program has stimulated interest in this issue. A new experimental approach by e-CALLISTO with 24 hours monitoring and further development of a model of the theory are hoping to meet the current knowledge about the Sun behaviour.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 11, 3; 243-256
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The Tendencies and Timeline of the Solar Burst Type II Fragmented
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/412634.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    sun
    low frequency
    solar radio
    burst
    type II
    type III
    e-CALLISTO
    Opis:
    We report the timeline of the solar radio burst Type II that formed but fragmented at certain point based on the eruption of the solar flare on 13th November 2012 at 2:04:20 UT. The active region AR 1613 is one of the most active region in 2012. It is well known that the magnetic energy in the solar corona is explosively released before converted into the thermal and kinetic energy in solar flares. In this work, the Compound Astronomical Low-frequency, Low-cost Instrument for Spectroscopy Transportable Observatories (CALLIISTO) system is used in obtaining a dynamic spectrum of solar radio burst data. There are eight active regions and this is the indicator that the Sun is currently active. Most the active regions radiate a Beta radiation. The active regions 1610, 1611 and 1614 are currently the largest sunspots on the visible solar disk. There is an increasing chance for an isolated M-Class solar flare event. It is also expected that there will be a chance of an M flare, especially from AR 1614 and 1610. Although these two observations (radio and X-rays) seem to be dominant on the observational analysis, we could not directly confirmed that this is the only possibility, and we need to consider other processes to explain in detailed the injection, energy loss and the mechanism of the acceleration of the particles. In conclusion, the percentage of energy of solar flare becomes more dominant rather than the acceleration of particles through the Coronal Mass Ejections (CMEs) and that will be the main reason why does the harmonic structure of type II burst is not formed. This event is one fine example of tendencies solar radio burst type III, which makes the harmonic structure of solar radio burst type II fragmented.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 12; 84-102
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The Gray Hoverman Antenna Construction for Meteor Observation
    Autorzy:
    Hamidi, Z. S.
    Hamidin, M. Azril
    Shariff, N. N. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/1188079.pdf
    Data publikacji:
    2016
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Meteor; forward - scattering technique; radio region; gray Hoverman antenna
    Opis:
    Meteors typically are small particles, normally no larger than a microscopic of sand, that enter our atmosphere at speeds of up to around 70 kilometers per second. Meteoroids are thought to originate in asteroids or comets, though some may be remnants from the early days of the Solar System. When a meteoroid striking the upper atmosphere, these meteors are produced by the streams of cosmic debris at extremely high speeds on parallel trajectories. Radio meteor scatter by forward scattering is a technique for observing meteors. A forward - scattering technique for radio meteor detection has been well-known for over 50 years ago. The Gray-Hoverman antenna has been designed by Doyt R. Hoverman and was invented in the 1950s covers from 300 to 3000 MHz and shows high performance for most Digital / HD channels broadcasting. The data obtained from the special software named 4nec2. From the results, the high gain obtained by the antenna is around 14.4 dBi at targeted range frequencies of 500MHz to 700MHz. it can be clearly observed that the designed antenna structure provides good amount of gain 14.4 dB, which is highly desirable for various applications. In future, the current Gray Hoverman’s antenna can be improved by adding 2 or more antennas which are structured in series or parallel depending on compatibility.
    Źródło:
    World Scientific News; 2016, 56; 21-32
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    An Analysis of Radiation Pattern and Standing-Wave Ratio (SWR) of the Gray Hoverman Antenna
    Autorzy:
    Hamidi, Z. S.
    Hamidin, M. Azril
    Shariff, N. N. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/1192610.pdf
    Data publikacji:
    2016
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Antenna
    radiation pattern
    radio region
    gray Hoverman antenna
    Opis:
    The radio antenna may be defined as the structure associated with the region of transition between a guided wave and free-space wave, or vice versa. Antennas convert electrons to photon, or vice versa. All involve the same basic principle that the radiation is produced by accelerated or decelerated charge. In order to enhance the reading and measurement, forward scattering technique is used to acquire more data. The aim of this paper is to highlight the theory part of radiation pattern and the analysis of this parameter. From the results, the radiation pattern of the antenna with a range of 700 MHz with the range of -11.0 dB till 10.6 dB. The results show that the maximum front lobe value is 14.4 dB. The back lobe value is 3.32 dBi and the side lobe is -18 dBi. As the gain of a directional antenna increases, the coverage distance increases, but the effective coverage angle decreases due to the lobes being pushed in a certain direction because there is a little energy on the back side of the antenna. The SWR is high in the range of 1-100 MHz with 106 but suddenly decreased to 10 at 100 MHz. The patterns are very dynamics and it less that 10 from 530 MHz to 1000 MHz. We conclude that The simulation results of this antenna structure are quite good as this antenna structure can work in particular frequency bands with a good amount of gain of 14.4 dBi, the SWR of below 10dBi, and impedance matching around 100 ohm.
    Źródło:
    World Scientific News; 2016, 60; 13-25
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Solar Burst Type IV Signature Associated with Solar Prominences on 20th January 2016
    Autorzy:
    Hamidi, Z. S.
    Hamzah, N.
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/1178518.pdf
    Data publikacji:
    2017
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Coronal Mass Ejections (CMEs)
    Sun
    X-ray region
    solar burst
    solar flare
    type IV radio region
    Opis:
    Proceeding from close association between solar eruptions, flare and CMEs, we analyze between burst at 980 MHz to 1270 MHz, recorded at the Blein, Switzerland on 20th January 2016. This burst indicates the emission radiation from the Sun from numerous high energy electrons in active region AR2484 and AR2487 forming a large prominence in that particular area. Solar prominences usually occur in loop shape and can last for weeks or months. This event allows us to investigate the electron density and drift rate of solar burst type IV During that time the Sun has the moderate number of sunspots with 55.The radio sources responsibly for IV appear to expand spherically through the solar corona after eject on y solar flare. This event shows a strong radiation in radio region, but not in X-ray region. This burst intense radio phenomena that follow with solar flares. It has a wide band and fine structure. It can be considered as an intermediate fast drift burst (IMDs). This fiber burst has a negative drift rate where the drift is interpreted by the group velocity of the whistler-mode waves. This burst appears is single SRBT III for approximately within 7 minutes with starting time is 8.23 UT. This burst duration is longer compared to the other events. It can be considered as a IV because it begins at the same time as the explosive phase of solar flare. The solar optical, radio and X-ray emission associated with these various energetic particle emissions as well as the propagation characteristics of each particle species are examined in order to study the particle acceleration and emission mechanisms in a solar flare. At the same time, the number of particles traveled a given path in reconnecting area falls exponentially with the increase of this path because of losses owing to a leaving of particles the acceleration volume due to drift.
    Źródło:
    World Scientific News; 2017, 70, 2; 111-121
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Space Weather: The Significance of e-CALLISTO (Malaysia) As One of Contributor of Solar Radio Burst Due To Solar Activity
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Monstein, C.
    Ibrahim, Z. A.
    Powiązania:
    https://bibliotekanauki.pl/articles/411980.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    sun
    radio emission
    solar radio burst
    Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy in Transportable Observatories (CALLISTO)
    solar flares
    Coronal Mass Ejections (CMEs)
    space weather
    Opis:
    The impact of solar activities indirectly affected the conditions of earth's climate and space weather in general. In this work, we will highlight a low cost project, however, potentially gives a high impact through a dedicated long-term and one of the most successful space weather project. This research is a part of an initiative of the United Nations together with NASA in order to support developing countries participating in „Western Science‟ research. At the beginning of 2007, the objective to monitor the solar activities (solar flares and Coronal Mass Ejections) within 24 hours all over the world has positively turned to reality. Realize how important for us to keep doing a research about the solar bursts, by using the new radio spectrometer, CALLISTO. This research is not only hoping to give a knowledge to the people about how the solar bursts are produced, the characteristics of every type of solar burst at the wide range (45 MHz to 870 MHz) but also the effect of the solar burst toward the Earth. By using the same CALLISTO spectrometer within the 45-870 MHz, designing and leading by Christian Monstein from ETH Zurich, Switzerland, this research project is the one of successful project under ISWI program. Malaysia becomes the 19th countries that involve this research. One of the advantages to start the solar monitoring in Malaysia is because our strategic location as equator country that makes possible to observing a Sun for 12 hours daily throughout a year. We strongly believe that Malaysia as one of contributor of solar activity data through E-CALLISTO network. This is a very good start for developing a radio astronomy in Malaysia.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 7; 37-44
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    An Analysis of Solar Burst Type II, III, and IV and Determination of a Drift Rate of a Single Type III Solar Burst
    Autorzy:
    Hamidi, Z. S.
    Ibrahim, M. B.
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/411732.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    sun
    solar burst
    type II,III,IV
    radio region
    X-ray region
    solar flare
    active region
    Opis:
    The main feature of solar radio type II, III and IV burst is outlined. In this event there are three combinations of bursts that related to the solar flare phenomenon on 6th July 2012. This event is one of good example to observe how far the influence of type II burst could impact the formation of type IV burst and III solar bursts. At first stage, it was observed that a sub-type of H burst form within 2 minutes before type IV solar burst form. The type IV burst is due to the eruption of active region AR 1515 with a fine structure (FS). We used a Blein CALLISTO data in this case. Further analysis also showed that the total energy of the burst are in the range of 4.875 × 10-25 J to 8.48 × 10-25 J and plasma frequency is equal to 1.24 × 104 Hz. Therefore, we could say that in this case, before the solar burst type III occurred, the ejection of CMEs already ejected.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 19, 2; 160-170
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A Case Study of Explosion A Single Solar Burst Type III and IV Due to Active Region AR1890
    Autorzy:
    Hamidi, Z. S.
    Ibrahim, M. B.
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/412554.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    sun
    solar burst
    III
    IV
    radio region
    X-ray region
    solar flare
    active region
    Opis:
    Using data from a BLEIN Callisto site, we aim to provide a comprehensive description of the synopsis formation and dynamics of a a single solar burst type III and IV event due to active region AR1890. This eruption has started since 14:15 UT with a formation of type III solar burst. To investigate the importance of the role of type III solar burst can potentially form a type IV solar burst, the literature review of both bursts is outlined in detailed. The orientation and position of AR1890 make the explosion of a class C-solar flare is not directly to the Earth. Nevertheless, it is clear that the interactions of others sunspots such as AR1893,AR1895,AR1896, AR1897 and AR1898 should be studied in detail to understand what makes the type III burst formed before the type IV solar burst.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 19, 2; 171-180
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    An Analysis of the Electron Density and Drift Rate of Solar Burst Type III During 13th of May 2015
    Autorzy:
    Ali, M. O.
    Hamidi, Z. S.
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/1192997.pdf
    Data publikacji:
    2016
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Coronal Mass Ejections (CMEs)
    Sun
    X-ray region
    radio region
    solar burst
    solar flare
    type III
    Opis:
    During 13th of May 2015, the solar wind is very high velocity, which is 733 kms-1 as compared to 367.5 kms-1. It is believed that the plasma–magnetic field interactions in the solar corona can produce suprathermal electron populations over periods from tens of minutes to several hours, and the interactions of wave-particle and wave-wave lead to characteristic fine structures of the emission. An intense and broad solar radio burst type II was recorded by CALLISTO spectrometer from 20-85 MHz. Using data from a the Blein observatory, the complex structure of solar burst type III can also be found in the early stage of the formation of type III solar burst type event due to active region AR 12339. The drift rate of solar burst type III exceeds 1.0 MHz/s with 6.318 x1012 e/m3 a density of electron in the solar corona. There were also 2 groups of solar radio burst type III were observed. This CME was detected at 08:36 UT which is 1and ½ hour after the solar burst detected. This event shows a strong radiation in radio region, but not in X-ray region.
    Źródło:
    World Scientific News; 2016, 31; 1-11
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    An Alternating of Solar Radio Burst Type III and IV of Thermal and Non-Thermal Plasma Radiation
    Autorzy:
    Hamidi, Z. S.
    Husien, Nurul Hazwani
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/1193005.pdf
    Data publikacji:
    2016
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Sun
    burst
    low frequency
    solar radio
    type III
    type IV e-CALLISTO
    Opis:
    A preliminary correlation study of the solar burst type III with a type Iv solar burst of has been made. On the basis of this study and in combination with the observation in radio emission, an interpretation of the mechanism of the occurrence of this event has been proposed. We have noted that an individual type III burst also can be observed at 13:54-13:58 UT from 500 MHz. Based on 3 days observation beginning from 31st March 2015, the solar activity is gradual increased. The highest solar flare can be observed is only a class of M8 flare. There was a CMEs event that directed to the Earth is detected. From the selected event, although theoretically solar radio burst type III is alternating with type IV solar burst. This huge explosion generated the M-class flare which can affect the Earth and satellites. The solar wind velocity recorded is 384.2 km/second while the density of protons is 3.6 protons/cm3. The total magnetic field during this event also quite big which is 4.6nT. The alternating of solar burst type III and IV would probably depends on the tendencies to form the CMEs event. The morphology of thermal and non-thermal flare plasma is of particular significance because it holds many important signatures of the energy release process.
    Źródło:
    World Scientific News; 2016, 31; 88-99
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The Development of Long Series of Quasi-Periodic Pulsation in Active Region AR 2297
    Autorzy:
    Sabri, S. N. U.
    Hamidi, Z. S.
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/1194014.pdf
    Data publikacji:
    2015
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    IV
    Sun
    X-ray region
    active region AR2222
    radio region
    solar burst
    solar flare
    Opis:
    This phenomena allow us to explore about suprathermal electron population that produced by plasma-magnetic field interactions in the solar corona about tens of minutes.The characteristics of the structures of the emission is influenced by wave-particle interaction and wave-wave interaction. The Callisto spectrometer recorded broadband of solar radio burst Type IV from 250-900 MHz. Using data from BLEN7M observatory, we aim to provide inclusive description about the formation and dynamics of solar radio burst type IV due to active region AR2297. About five minutes, the events revealed strong pulsations and “broad patterns” with details of solar radio burst type III with presence of CMEs. AR2297 is the most active region which produced X2-Class solar flares. The speeds of solar wind exceeds 376.0 km/second with 4.0 g/cm3 density of proton in the solar corona. The radio flux shows 121 SFU. Furthermore, there are two active regions, AR2298 and AR2299 also presents in the X2-class solar flares. Active region AR2297 have unstabe ‘Beta-Gamma-Delta’ magnetic fields thet habor energy for M class to X2- class eruptions. As a conclusion, we conclude that Sun activities are more active to achieve maximum cycle at the end 2015. Solar flares on 11th of March 2015 showed long series of quasi-periodic pulsation that deeply modulate a continuum and its drifting toward lower frequency. The corona extends from the top of a narrow transition region to Earth and has a temperature millions of degrees that still mysterious properties.
    Źródło:
    World Scientific News; 2015, 9; 59-69
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    An Analysis of Antenna Temperature and Radar Cross Section of Log Periodic Dipole Antenna
    Autorzy:
    Hamidi, Z. S.
    Saad, M. Azren Mat
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/1192599.pdf
    Data publikacji:
    2016
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Sun
    Log Periodic Dipole Antenna
    type III
    radio region
    antenna temperature radar cross section
    Opis:
    The LPDA antenna because it is very suitable and economic amount the types of antennas. It consists of an array of dipoles in which their lengths and spacing are arranged in a log periodic manner, but not all elements in the system are active on a single frequency of operation. The temperature or Antenna Noise Temperature depends on its gain pattern and the thermal environment that it is placed in. We need to design an antenna that can detect the data and monitor the solar burst type III in radio region. It must be sensitive to a broad frequency range and angular distribution of the incident radio pulse and capable to handle the noise issue that is necessary to gain the pure signal. With large instantaneous bandwidths and high spectral resolutions, these instruments will provide increased imaging sensitivity and enable detailed measurements of the dynamic solar burst. For standardized the time, GPS clock is used to control the sampling time of the spectrometer and a tracking controller control the antenna direction. In conclusion, LPDA is the most practical antennas provide general broadband transmission and reception in a wide range of frequency.
    Źródło:
    World Scientific News; 2016, 55; 126-136
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The zigzag pattern construction of Log Periodic Dipole Antenna Based on Rumsey’s Principle
    Autorzy:
    Hamidi, Z. S.
    Saad, M. Azren Mat
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/1188094.pdf
    Data publikacji:
    2016
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Log Periodic Dipole Antenna
    zigzag pattern
    solar burst
    radio region
    Rumsey’s principle
    Opis:
    The log-periodic dipole array (LPDA) consist of an array of dipoles in which there have a different lengths and spacing. The wire may be straight or it may be strung back and forth between trees or walls just to get enough wire into the air; this type of antenna sometimes is called a zigzag antenna. Rumsey’s principle requires that the locations of all elements be specified by angles rather than distances, because of this the log periodic dipole array must be correspondingly longer to get very wide bandwidths and gives a very high data rate transmission. The significance of this study is to understand how do the LPDA can be used to monitor solar activities of the sun using the LPDA antenna. The characteristics that need to be considered during construct this antenna is the radiation pattern, polarization, operation of the frequency band, gain and efficiency of an antenna which indicates the power or field strength radiated in any direction relative to that in the direction of maximum radiation. The arrangement of elements in increasing order from the top of the antenna until the bottom part of antenna. Our designed antenna was constructed using aluminum for the further investigation, we can use a copper and check the difference between two of this element. For this study, we just analyzed the source of RFI using this antenna and for the further analysis, we can use this antenna to monitor the solar burst.
    Źródło:
    World Scientific News; 2016, 56; 146-157
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Relativistic Energy Associated with a Moving Fiber Burst Type μIV Associated with The Class A Solar Prominence
    Autorzy:
    Hamidi, Z. S.
    Norsham, N. A. M.
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/1194133.pdf
    Data publikacji:
    2016
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Coronal Mass Ejections (CMEs)
    Sun
    X-ray region
    solar burst
    solar flare
    type IV radio region
    Opis:
    The relativistic energy electron emission is found to occur only during proton events. Solar prominences usually occur in loop shape and can last for weeks or months. This event allows us to investigate the electron density and drift rate of solar burst type IV During 21st September 2015. During that time the Sun has the highest number of sunspots. The radio sources responsibly for Ivm appear to expand spherically through the solar corona after eject on y solar flare. This event shows a strong radiation in radio region, but not in X-ray region. This burst intense radio phenomena that follow with solar flares. It has a wide band structure from 1412-1428 MHz. It can be considered as an intermediate f drift burst (IMDs). This fiber burst has a negative drift rate where the drift is interpreted by the group velocity of the whistler-mode waves. Their bandwidth is approximately 2% of the emission frequency. The are accompanied a parallel-drift absorption band in the background continuum radiation. The occurrence of the event is interesting in many aspects which is also in ZSIS site. From the dynamic spectra of the CALLISTO, it can be observed that there a moving type IV burst. This burst appears is single SRBT III for approximately 16 minutes at 708UT till 716UT. This burst duration is longer compared to the other events. It can be considered as a Ivμ because it begins at the same time as the explosive phase of solar flare. The solar optical, radio and X-ray emission associated with these various energetic particle emissions as well as the propagation characteristics of each particle species are examined in order to study the particle acceleration and emission mechanisms in a solar flare. At the same time, the number of particles traveled a given path in reconnecting area falls exponentially with increase of this path because of losses owing to a leaving of particles the acceleration volume due to drifts.
    Źródło:
    World Scientific News; 2016, 57; 11-20
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The Formation of Fundamental Structure of Solar Radio Burst Type II Due X6.9 Class Solar Flare
    Autorzy:
    Zainol, N. H.
    Hamidi, Z. S.
    Shariff, N. N. M.
    Ali, Marhana Omar
    Husien, Nurulhazwani
    Sabri, S. N. U.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/1190115.pdf
    Data publikacji:
    2016
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Sun
    solar burst
    type II
    radio region
    X-ray region
    solar flare
    Coronal Mass Ejections (CMEs)
    Opis:
    A vigorous solar flare event marked on the spectrometer of the CALLISTO data, being one of the highest solar flare event that successfully detected. The formation of solar burst type II in meter region and their associated with X6. 9-class solar flares have been reported. The burst has been observed at the Blein Obsevatory, Switzerland, which detected by the Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy and Transportable Observatory (CALLISTO) system in the range of 170-870 MHz in the two polarizations of left and right circular polarization. It occurred between 08:01 UT to 08:08 UT within 7 minutes. The Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy and Transportable Observatory CALLISTO spectrometer is a solar dedicated spectrometer system that has been installed all over the world to monitor the Sun activity in 24 hours. The growth of this burst is often accompanied by abundance enhancement of particles which may take the form of multiple independent drifting bands or other forms of fine structure. Due to the results, the drift rate of this burst is 85.71 MHz s-1, which is considered as a fast drift rate. The burst detected using CALLISTO also being compared to results detected by X-ray GOES data. Both different electromagnetic spectrum shows the exact time. The observations of the burst being discussed in details.
    Źródło:
    World Scientific News; 2016, 35; 30-43
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The Enlargement of Type II Burst After Type III at AR 12522 on 16th March 2016 In Conjunction With Flare-Related Coronal Mass Ejections Event
    Autorzy:
    Husien, Nurulhazwani
    Hamidi, Z. S.
    Shariff, N. N. M.
    Ali, M. O.
    Zainol, N. H.
    Sabri, S. N. U.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/1178545.pdf
    Data publikacji:
    2017
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Coronal Mass Ejections
    Sun
    X-ray emission
    Opis:
    On 16th March 2016 the solar radio burst type II is recorded to appear on spectrograph after the type III formation. These two bursts related to the Coronal Mass Ejections (CMEs) event that recorded by the SOHO spacecraft several minutes before the formation of Type III on the spectrograph. It has been reported that the Type III burst a fast drift compared to the Type II burst. In this paper, the calculation has been proved that the type III burst has a higher drift rate compared to Type II. These two events of Type II and III burst also has been contributing to the formation of C class flare with magnitude of C2.2 It is also proven that the type III burst has a fast drift rate compared to type II burst. In this case, the type III has a fast drift rate of 81% compared to the type II burst. During this event, the active region AR 12522 erupted the C-class X-ray emission with magnitude of C2.2 contribute to these type III and II burst
    Źródło:
    World Scientific News; 2017, 70, 2; 230-240
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Heart-shape Active Region 2529 Producing Strong M6.7 class Solar Flare and Gradual Coronal Mass Ejections
    Autorzy:
    Hamidi, Z. S.
    Omar Ali, M.
    Nurul, Hazwani Husien
    Sabri, S. N. U.
    Zainol, N. H.
    Shariff, N. N. M.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/1179601.pdf
    Data publikacji:
    2017
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Gradual Coronal Mass Ejections
    Heart-shape active region
    Sun
    X-ray region
    solar flare
    Opis:
    The Centre of the Sun is very important to be study because this layer is where the nuclear reaction will be occurred. During large event pre-flare usually continues a few minutes and followed by impulsive phase about 3 to 10 minutes. Solar storms such as solar flare and Coronal Mass Ejections are frequently occurred on the area of the Sun that have strong magnetic field or known as active region The release of the stored free magnetic energy that probably drives a CME can take many forms including (predominantly) mechanical in the form of an expanding CME and erupting filament, electromagnetic emission in the form of a flare, and also in the acceleration of energetic particles, magnetic field reconfiguration and bulk plasma motion. In this study, the data of active region of the Sun was taken from official website of the Langkawi National Observatory. The image of the active region was observed by using 11-inch Celestron telescope with solar filter. This data confirms that there was a strong M class of solar flare during the day due to eruption of AR 2529 was occurred on 18th of April. From the x-ray flux data also, it can be observed that few days before M6.7 class solar flare occurred, there were several C classes of flare. The evolution of small AR 2529 to a big heart-shape forms an eruption that producing strong M6.7 class of flare and three gradual CMEs. This strong flare caused significant impact around the high technologies of Pacific Ocean by fading the signal at frequencies below 15 MHz.
    Źródło:
    World Scientific News; 2017, 74; 181-193
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Production of Coronal Mass Ejections in Relation With Complex Solar Radio Burst Type III Correlated With Single Solar Radio Burst Type III
    Autorzy:
    Hussien, Nurul Hazwani
    Hamidi, Z. S.
    Ali, M. O.
    Sabri, S. N. U.
    Zainol, N. H.
    Shariff, N. N. M.
    Moinstein, C
    Powiązania:
    https://bibliotekanauki.pl/articles/1192988.pdf
    Data publikacji:
    2016
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Sun
    Solar radio burst
    type III
    single Solar Radio Burst Type (SRBT) III
    complex Solar Radio Burst Type (SRBT) III
    Coronal Mass Ejection (CMEs)
    magnetic reconnection
    Opis:
    The complex solar radio burst type III is very related to generation of Coronal Mass Ejections (CMEs). In a previous study, they deduced that the burst was produced by electron beams accelerated in blast wave shocks and injected along open magnetic field lines, similar to the herringbone bursts at metric wavelengths. Usually, if there is another solar flare recorded during complex solar radio burst type III it should be type II burst. Different for this event, the single solar radio burst recorded occur 8 minutes 30 seconds before the complex solar radio burst type III. The Coronal Mass Ejections also recorded occurred 7 hours before the single and complex solar radio burst type III. It is noted that CMEs occurred several hours before this event recorded by the SOHO websites.It is proved that the production of coronal mass ejection contributed to the production of complex solar radio burst type III.
    Źródło:
    World Scientific News; 2016, 36; 96-108
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Geo-effective Disturbances from the “Beta-Gamma-Delta” Magnetic Fields on Active Region AR 2403
    Autorzy:
    Sabri, S. N. U.
    Hamidi, Z. S.
    Shariff, N. N. M.
    Monstein, C.
    Zainol, N. H.
    Ali, M. Omar
    Hussien, Nurul Hazwani
    Powiązania:
    https://bibliotekanauki.pl/articles/1192069.pdf
    Data publikacji:
    2016
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Sun
    Solar Radio Burst Type IV
    X-ray region
    Solar flare
    active region AR 2403
    Opis:
    This moving solar radio burst type IV, which lies in between 980 – 1260 MHZ was observed using Compound Astronomical Low-Cost Low- Frequency Instrument for Spectroscopy and Transportable Observatory (CALLISTO) spectrometer and will discussed in detail. CALLISTO system was used and the data were recorded. From BLEN5M’s Radio Flux Density data, it shown that a brief description of the formation of a dynamic formation of solar radio burst type IV due to an active region, AR 2403. This event proved that solar radio burst type IV has a broadband continuum features and has strong pulsations in some range of time. In this event it was took about 8 minutes and it can be high in possibility solar flare and CMEs event followed due to this event. AR 2403 remained active and produced an X- class solar flares and it showed “Beta- Gamma-Delta” magnetic field that gives solar flares which can make geo-effective disturbance to our earth satellite and we have to investigate how plasma – magnetic field in the solar corona which can produce suprathermal electron pulsation about 8 minutes. In this event, it has solar wind speed in 364.8 km/sec and solar wind density in 11.0 protons/cm3.
    Źródło:
    World Scientific News; 2016, 37; 1-11
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Emergence of an Impulsive CMEs Related To Solar Radio Burst Type III Due To Magnetic Filament Eruption
    Autorzy:
    Ali, M. Omar
    Shariff, N. N. M.
    Hamidi, Z. S.
    Husien, Nurul Hazwani
    Sabri, S. N. U.
    Zainol, N. H.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/1192085.pdf
    Data publikacji:
    2016
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Sun
    Coronal Mass Ejections (CMEs)
    solar burst type III
    magnetic filament
    Opis:
    During solar activity the energy particles of the sun released due to solar flare, Coronal Mass Ejections (CMEs), coronal heating as well as sunspot. Solar radio burst will be observed in the presence of solar activity such solar flare, CMEs and solar prominence as the indicator for those events to happen. During the peak of solar cycle, the filaments are present due to the active magnetic field and solar storm’s explosion. This type of solar radio burst normally can be seen in the phase of impulsive solar flare. Therefore, it is crucial to understand field line connectivity in flare and the access of flare accelerated particle to the earth. In this study, we highlighted on the observation of solar radio burst type III on 9th of May at 05:31 UT till 05:44 UT. The event was successfully recoded by e-CALLISTO using BLEINSW radio telescope. The Solar Radio Burst Type III that had been observed was related to the Coronal Mass Ejections and the mechanisms that trigger the events have been discussed. It is shown that the CMEs is believed to happen because of the magnetic filament that connected to active region (AR) 2339 was erupted, and combination of two wild filament produced a bright CMEs. Fortunately, the expanding cloud does not appear to be heading for earth.
    Źródło:
    World Scientific News; 2016, 37; 168-178
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Investigation on a Broken Solar Burst Type II during High Activities in AR1613 on 13th November 2012
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Monstein, C.
    Zulkifli, W. N. A. W.
    Ibrahim, M. B.
    Arifin, N. S.
    Amran, N. A.
    Powiązania:
    https://bibliotekanauki.pl/articles/411666.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    sun
    low frequency
    solar radio
    burst
    type II
    type III
    e-CALLISTO
    Opis:
    The present article is an attempt to analyze the solar burst Type II observations based on solar flare and Coronal Mass Ejections (CMEs) events. We choose an intriguing type II radio burst with a velocity of 1193 kms-1 that occurred on 2012 November 13 at 2:04:20 UT. In this case, the study of solar radio burst type III is of paramount importance because of the fact that it helps to gain an insight of generation mechanisms of solar flare and Coronal Mass Ejections (CMEs) phenomena. Here, we have got a reasonably clear idea of the various forms under which the type III continuum emission may appear and potentially form a type II burst. However, in this case, the Type II solar burst only successfully forms a fundamental structure within the first few minute period, but broken suddenly before evolve a harmonic structure. This phenomenon is very interesting to be tackled and study. How the burst suddenly broken is still ongoing research seems the event is very rare and hard to be proved. There are a few questions that cause this unique situation which related to: (i) the intensity and duration of type III burst which also related to the classification of solar flare (ii) the probabilities CMEs to occur during that time and also the factor of the total amount of massive burst that exploded, Thus, we can conclude that the solar burst type III event still tells us an enigmatic characteristic from time to time due to the relationship of energetic particles and streams of particles with coronal magnetic fields and the pattern of Sun activity due to the 24th solar cycle. It might an interesting to study in detail the main factor that caused the Type II solar burst broken. Indirectly, it might because of the very intense of solar flares that make the percentage of energy of solar flare become more dominant rather than the acceleration of particles through the Coronal Mass Ejections. Thus, we realize that the potential energy during this event is higher than the kinetic energy of the particles.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 9; 8-15
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Observation of the Radio Frequency Interference (RFI) at the National Space Centre, Malaysia
    Autorzy:
    Hamidi, Z.S.
    Shariff, N.N.M.
    Monstein, C.
    Wan Zulkifli, W.N.A.
    Ibrahim, M.B.
    Arifin, N.S.
    Amran, N.A.
    Powiązania:
    https://bibliotekanauki.pl/articles/11076.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    observation
    Radio Frequency Interference
    National Space Centre
    Sun
    astronomy
    solar monitoring
    e-CALLISTO system
    Malaysia
    Opis:
    Important results of the Radio Frequencies Interference (RFI) at the National Space Centre, Sg Lang Selangor, Malaysia has been reported. In order to make sure that the data of solar monitoring in radio region is reliable, we need to study the variation of interference and the possible sources that contribute to this interference. This data has been taken from 1-2000 MHz at the main site of installation e-CALLISTO system. The study is one of a main part of an initiative of e-CALLISTO networking research in order to identify the main RFI sources and to monitor continuously the behavior of the RFI at the site. Our main objective is to qualify the potential of monitoring a continuous radio emission of the Sun. This work is also an initiative of the International Space Weather Initiative (ISWI) project where Malaysia is one of the countries that joined the e-CALLISTO network. Due to our results this site showed the positive impact for the solar monitoring purpose. It is hoped that the survey will continue from time to time in a consistent mode so that any polluted signal for radio astronomy purpose can be protected. Overall, we can still get a good solar burst data, especially at 40-400 MHz. Perhaps, we can contribute the good data for solar burst monitoring towards the maximum cycle beginning the end of this year 2013.
    Źródło:
    International Letters of Natural Sciences; 2014, 05
    2300-9675
    Pojawia się w:
    International Letters of Natural Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Solar Radio Burst Type III due to M 2.9 Class Flare with a Geomagnetic Disturbance
    Autorzy:
    Hamidi, Z. S.
    Ali, M. O.
    Shariff, N. N. M.
    Monstein, C.
    Zainol, N. H.
    Hussien, Nurul Hazwani
    Ramli, Nabilah
    Farid, M. S.
    Powiązania:
    https://bibliotekanauki.pl/articles/1190207.pdf
    Data publikacji:
    2016
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    solar radio burst
    solar storm
    flare
    geomagnetic disturbance
    Opis:
    Varying forms of solar radio burst were classified by their frequent changes in time, which are known as drift rate. There are 5 types of radio emission were named type I, II, III, IV and V. This paper is highlighted on the type III event which occurred on 27th August 2015. In the IP medium, type III solar radio burst can be classified in three different groups which representing three different situations of electron beam production and propagation which are isolated, complex and storm type III burst. The most powerful manifestation of solar activity is solar flare together with coronal mass ejections, eruptive prominences and the solar wind are the solar events which affect the earth's atmosphere and can cause geomagnetic disturbance. In this study, the effect of M class flare with solar radio burst type III was investigated. During the day, the solar wind proton density seems to be high which is 8.4 protons/cm3 and accompanied by normal solar wind speed of 348.7 km/Sec. Spaceweather.com reported that there is one sunspot was detected (AR2403) and M class of the flare was detected during the day at 0544 UT. The data geomagnetic signal shows that during the day only geomagnetic disturbance that occur no such geomagnetic storm since the sunspot not facing the earth directly.
    Źródło:
    World Scientific News; 2016, 44; 155-167
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    An X-ray Observations of A Gradual Coronal Mass Ejections (CMEs) on 15th April 2012
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Monstein, C.
    Wan Zulkifli, W. N. A.
    Ibrahim, M. B.
    Arifin, N. S.
    Amran, N. A.
    Powiązania:
    https://bibliotekanauki.pl/articles/411850.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Sun Coronal Mass Ejections (CMEs)
    solar corona
    solar flare
    solar cycle
    Opis:
    In the present work, we will highlight the solar observation during 15th April 2012, solar filament eruption which is accompanied by an intense and gradual Coronal Mass Ejections (CMEs) The explosion of CMEs was observed at 2:12:06 UT and also can be observed by the Solar Dynamics Observatory (SDO) with an Active Region AR1458 is crackling with C-class solar flares. The solar flare class B3 and C2 were observed beginning 2241 UT and 0142 UT. The event is considered as second largest CMEs been detected since five years. Although the solar activity within a few days is considered quite low and there are no proton events were observed at geosynchronous orbit., the is still an unexpected explosion of CMEs can be occurred. The radio flux number (10.7 cm) exceeds 102 with the number of sunspot and area of sunspot increased to 77 and 270. The velocity of CMEs was calculated based on the LASCO2 data. From the results, it is clearly seen that the range of the velocity is between 200 kms-1 to 2000 kms-1. This wide of range proved that the mechanism of the CMEs is a gradual process. The explosion of CMEs velocity is located from 80º - 255º from North of the Sun. We can then conclude that currently, the rearrangement of the magnetic field, and solar flares may result in the formation of a shock that accelerates particles ahead of the CMEs loop and an active region play an important character in this event.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 8; 13-19
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The Tendencies Group Type III Burst Form Type II Burst During Low activity
    Autorzy:
    Hamidi, Z. S.
    Mokthtar, Fatin Nabila
    Shariff, N. N. M.
    Ali, Marhana Omar
    Husien, Nurulhazwani
    Sabri, S. N. U.
    Zainol, N. H.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/1191365.pdf
    Data publikacji:
    2016
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Coronal Mass Ejections (CMEs)
    X-ray region
    radio region
    solar burst
    sun
    sun type II
    sun type III
    Opis:
    Using the e-CALLISTO network radio observations on 1st June 2015, we present an analysis of the complex type III and type II solar radio bursts during low activity. This event occurred on 1st July 2015 at 13:52 UT (complex solar burst type III) and 13:40 UT - 13:44 UT (solar burst type II). Solar burst type detected at (i) BIR, (ii) BLENSW, (iii) Essen, (iv) Glascow (v) Osra, (vi) Rwanda. The spectral shape consists of high flux densities at meter wavelengths. The energy going into plasma heating during each flare was estimated by computing the time evolution of the energy content of the thermal plasma and obtaining the peak value. This constitutes a lower limit to the thermal energy, since it does not account for the cooling of the plasma prior to this time nor to any heating at later times. It is also believed that the meter wavelength branch of the this type III spectrum may be attributable to second-phase accelerated electrons to form type II burst. There are four sunspots of the active regions (AR2355, AR2356, AR2357, and AR2358) during this event. The solar wind recorded during the event is 342.4 km/s and the density of the proton recorded is 4.1 protons/cm3. Moreover, the are some evidence that radio-quiet CMEs mostly came from the edges of the sun. The main goal of this study was to determine whether is there any possibilities that the radio burst can be formed even the Sun is at low activity and this event is one of the candidate events.
    Źródło:
    World Scientific News; 2016, 34; 121-134
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The Development of the X2-Class of flares with Presence of Type IV burst and Single Type III burst in Low Frequency (20-85 MHz) on 5th May 2015
    Autorzy:
    Sabri, S. N. U.
    Hamidi, Z. S.
    Shariff, N. N. M.
    Zainol, N. H.
    Syazwan, Nabilah Ramli
    Ali, Marhana Omar
    Husien, Nurulhazwani
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/1191466.pdf
    Data publikacji:
    2016
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Sun
    solar burst
    III
    IV
    X-ray region
    solar flare
    Active Region 2335
    Opis:
    The plasma-magnetic field interaction in the solar corona is caused exploration of suprathermal electron population have been made to study about the phenomena solar radio burst. This burst only took about approximately 2 minutes to produce X2- class of solar flares which occurred at 22:10 UT till 22:11UT. The wave-wave interaction and wave-particle interaction influenced the characteristic structures of the emission. The CALLISTO spectrometer has been used to detect and record the Type IV and Type III occurred during 22:07UT till 22:11 UT and it only took about 3.30 minutes to occur. The range of frequency of this burst 20-85 MHz and data is from ROSWELL-NM observatory. With the presence of the data, we aim to determine the causes of the Solar Radio Burst Type IV produced Type III burst in several minutes and describe briefly about the formation and dynamics of solar radio burst type IV occurred on active region, AR2335 which also produced beta-gamma magnetic field. This event showed the strong pulsation and a broadband pattern with details about Type IV burst, then Type III burst present in fast drift. AR 2335 is the most active region and produced X2-class of solar flares which has solar wind speed about 361.6km/second and proton density about 4.3 protons/cm3 in the solar corona. AR 2335 harbor energy for X2-class from 6-H to 24-H observation on X-Ray solar flares have been recorded. The data showed that it has a strong energy electrons presence during the burst occurred in the active region and this class of solar flares are more powerful which has potential to cause radio blackout and long lasting space weather storms. As the conclusion, the sun activity showed on 5th May 2015 has quasi-periodic pulsation that has continuum and drift in lower frequency. The temperature that corona took to extend from the top of a narrow transition region still be as mysterious properties.
    Źródło:
    World Scientific News; 2016, 40; 188-198
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The Solar Radio Burst Type II Correlated With Minor CME Contributes to The Production of Geomagnetic Disturbance
    Autorzy:
    Husien, Nurulhazwani
    Hamidi, Z. S.
    Ali, M. O.
    Zainol, N. H.
    Sabri, S. N. U.
    Shariff, N. N. M.
    Faid, M. S.
    Ramli, Nabilah
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/1192691.pdf
    Data publikacji:
    2016
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Solar radio burst
    solar radio burst type II
    Coronal Mass Ejections
    geomagnetic disturbance
    Opis:
    The solar radio burst type II on 4th November 2015 was associated with minor CME that not lead towards the Earth. This clear type II burst recorded on spectrographs detected by the antenna in several locations (Gauri, Almaty, Kasi and Ooty) were obtained from CALLISTO website. The average time of the burst occurred are around 03:24 UT until 03:28 UT with the clear minor CME emerged recorded by SOHO at 03:12 UT. Although it just a minor CME but it is still giving the effect on Earth as it contributes to geomagnetic disturbance on the Earth during that day. The affected region reported by The Local news is Sweden, where the radar system for aviation was not clear, but it is back to normal after a few hours later. This geomagnetic disturbance is powerful enough that may cause the satellite damage, endanger astronauts and produce destructive surges on power grids.
    Źródło:
    World Scientific News; 2016, 46; 165-175
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    An Analysis of Active Regions 11036 Characteristics Leads To Solar Flare Class C7.2 Phenomena
    Autorzy:
    Zainol, N. H.
    Hamidi, Z. S.
    Husien, Nurulhazwani
    Ali, M. O.
    Sabri, S. N. U.
    Shariff, N. N. M.
    Faid, M. S.
    Monstein, C.
    Ramli, Nabilah
    Powiązania:
    https://bibliotekanauki.pl/articles/1192106.pdf
    Data publikacji:
    2016
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Solar Radio Burst Type II
    solar flare
    Callisto network
    active region
    Opis:
    The solar flares are generated from electromagnetic radiation which is sudden oscillation of the stored energy in the magnetic field of the sun. Flares are categorized according to their brightness as C, M and X, where X is the brightest. The X class flares caused a long-time solar storm and ionospheric radio waves sparkling. The moderate level M class flares mostly effect polar cups and cause short-time radio sparkling. However, the C class flares are weaker than the X and M flares. In this work, we present an active region from the disturbance of magnetic field on the area of the Sun and may lead to powerful event if the magnetic field become stronger. The CALLISTO system network that has been installed in Gauri, India observed data that contain Solar Radio Burst Type II (SRBT II) occurred on 22nd December 2009 at 04:57 UT to 05:02 UT. Five active regions were obtained from online data via internet from the Space Weather website and the Solar Monitor website. All data and information from these sources assist in analyze of the phenomena. The magnetic field and X-ray flux, proton density increase the possibilities that SRBT II observed by CALLISTO network to generate powerful solar flare. When X-ray flux level was at maximum, then solar flare was at peak point. However, solar activity level was low because among of five active regions present, only one C-class flare event occurred. The most active region that contributes this event is an AR11036 with C-class flare.
    Źródło:
    World Scientific News; 2016, 45, 2; 80-91
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The Correlation between Solar Flare Phenomena in an X-ray Region and Radio Flux Measurement from January to September 2010
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Ali, M. F.
    Monstein, C.
    Zulkifli, W. N. A. W.
    Ibrahim, M. B.
    Arifin, N. S.
    Amran, N. A.
    Powiązania:
    https://bibliotekanauki.pl/articles/411743.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    sun
    chromospheres
    flares
    radio flux
    solar activity
    Opis:
    A short term variation of solar flare in nine months (January 2010 to September 2010) is presented. This paper review and analyze the correlation between radio flux strength measurement and solar flare in the X-ray region. The radio flux measurement data were taken from the National Research Council; Ottawa while hard X-ray emission observed by Royal Observatory of Belgium. The overall range of solar radio flux recorded in this study ranging from 68 x 10-22 Wm-2Hz-1 to 96 x 10-22 Wm-2Hz-1. As there was no class of an X of solar flare reported at all in this study, we can confirm that there are no major effects that happened on Earth and outer space such as Coronal Mass Ejections (CMEs) and solar storms. We concluded that the Sun shows a very minimum activity towards 24th solar cycle.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 9; 84-92
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Current Situation of Radio Frequency Interference (RFI) Profile at Outdoor and Indoor Sites of Faculty of Applied Sciences, UITM, Malaysia
    Autorzy:
    Hamidi, Z. S.
    Nizamudin, Nur Izzani
    Shariff, N. N. M.
    Syazwan, M.
    Husien, Nurulhazwani
    Ali, M. O.
    Zainol, N. H.
    Ramli, Nabilah
    Sabri, S. N. U.
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/1191429.pdf
    Data publikacji:
    2016
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Radio Frequency Interference (RFI)
    radio astronomy
    RFI sources
    Opis:
    This Radio Frequency Interference (RFI) study is currently one of a main sub-research in radio astronomy in Malaysia. The main objective of this monitoring is to test and qualify the potential of radio astronomical sources that can be observed in Malaysia generally. Analysis process focuses at indoor and outdoor of Faculty of Applied Sciences, UITM Shah ALAM, Malaysia (latitude: 03°06.534’N, longitude: 101°50.396’E). There are three mobile network communications that operate at the upper band frequency of 1800MHz, which are Maxis (1805-1830 MHz), Celcom (1830-1855 MHz) and Digi (1855-1880 MHz) for GSM/LTE network. We observed that both sites having the highest and second highest peak at the same frequency of 420 MHz and 1835 MHz with the same source, which were due to mobile application followed by the lowest peak due to radio navigation satellite. We verified that the source of RFI of 1835 MHz at the Faculty of Applied Sciences may come from Celcom mobile telecommunication network signal because there is transmitter on top of two Celcom towers. This observation must be continuously done to ensure that RFI level does not increase drastically and to ensure that allocation spectrum band that was reserved for radio astronomy activities was always protected.
    Źródło:
    World Scientific News; 2016, 40; 23-33
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Coronal Electron Density Distribution Estimated from Meter Type II Radio Bursts and Coronal Mass Ejections
    Autorzy:
    Yusof, N. S.
    Hamidi, Z. S.
    Norsham, N. A.
    Jafni, A. I.
    Kahlid, N. M.
    Hamdan, M. N.
    Kamaruddin, Farahana
    Tahar, Muhammad Redzuan
    Monstein, C.
    Shariff, N. N. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/1192681.pdf
    Data publikacji:
    2016
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    coronal mass ejection
    Type II radio burst
    electron density distribution
    e-CALLISTO
    Opis:
    In this paper, we investigate the characteristic coronal mass ejection and Type II radio burst, we calculated the drift rate of Type II Radio burst and determined the electron density distribution from a Coronal Mass Ejections. The data were taken from website e-CALLISTO, Space Weather, SolarHam and also from the Langkawi National Observatory, National Space Agency, Langkawi Kedah, Malaysia. All the data collected on 15th March 2015, 4th November 2015 and 16th December 2015. On 16 March 2015, the events were associated with slower C9 solar flare and CME. For this week, the events were causing radio blackouts on Earth. On 4 November 2015, the events were associated with M1.9 solar flare, CME and Solar burst Type II. The value of the solar wind was 570.4 km/Sec and value for radio sun was 124 sfu. For drift rate, we calculated the value for sites in Sri Lanka (ACCIMT-SRI), Ooty, India (OOTY), Indonesia (INDONESIA) and Kasi, South Korea (KASI) at between 0324 to 0328 UTC. In South Korea was highest drift rate, which is 1.397 MHz/s. Also, at HB9SCT, Switzerland (HB9SCT), Humain, Belgium (Humain), Daro, Germany (Daro-VHF) and TCD in Birr, Ireland (BIR), we calculated the drift rate of solar burst Type II between 1200 until 1203 UTC. In Belgium had the highest value of the drift rate to compare at other sites. Harmonic pattern was also appeared for all these sites. On 16th December 2015, this event associated with C6.6 solar flare and CME. These events give an impact on the earth geomagnetic field which is formed of aurora because of the combination of both events that trigger geomagnetic storming.
    Źródło:
    World Scientific News; 2016, 46; 19-35
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The Progression of Active Region with the Formation of Group and Complex Solar Radio Burst Type III on 31st August 2015
    Autorzy:
    Hamidi, Z. S.
    Norsham, N. A.
    Mazlan, Muzamir
    Yusof, N. S.
    Jafni, A. I.
    Kahlid, N. M.
    Hamdan, M. N.
    Kamaruddin, Farahana
    Tahar, Muhammad Redzuan
    Monstein, C.
    Shariff, N. N. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/1182942.pdf
    Data publikacji:
    2016
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    solar prominences
    complex solar radio burst
    type iii
    ar2403
    e callisto
    Opis:
    In this event, a solar radio burst in the range of 45-165 MHz with energy of 〖2.982 x 10〗^(-26) to 〖1.093 x 10〗^(-25) Joule with 0.8 MHz/ second have been correlated with the optical solar prominence. In combination of the optical, radio and X-ray observation, the occurrence of the event has been proposed. The active region of the prominence was AR2403. An individual type III burst was observed at 19:40 UT. The burst lasts for 15 minutes with a drift rate of 0.8 MHz/s. This burst was recorded by the Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy and Transportable Observatory (CALLISTO) at Almaty Site. From 29th August 2015 onwards, the total magnetic flux increases gradually to over four-fold the initial value during development and levels off around 29th August 2015. It was found that B3 solar flare, followed by a slow coronal mass ejection (CME), is released from NOAA 2403 on 31st August 2015. The region is beyond -30 longitude at the time of the flare, making it impossible to reliably measure any magnetic properties involving gradients. The overall increase of Beff prior to the flare is indicative of an increase in polarity mixing within the AR, which has been shown to be related to flaring. Understanding of the exact nature of the initiation of these events is still incomplete.
    Źródło:
    World Scientific News; 2016, 49, 2; 272-282
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Comparison of the Optical Image of the Solar Prominence with the Formation of Solar Radio Burst Type III on 3rd September 2015
    Autorzy:
    Hamidi, Z. S.
    Norsham, N. A.
    Mazlan, Muzamir
    Yusof, N. S.
    Jafni, A. I.
    Kahlid, N. M.
    Hamdan, M. N.
    Kamaruddin, Farahana
    Tahar, Muhammad Redzuan
    Monstein, C.
    Shariff, N. N. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/1192670.pdf
    Data publikacji:
    2016
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    solar prominences
    solar radio burst
    type III
    AR2407
    e CALLISTO
    Opis:
    Solar radio burst in the range of 220 - 400 MHz have been correlated with the optical solar prominence phenomena covering the presence sunspot minimum. In combination of the observation in radio emission and the basis of this study, the occurrence of the event has been proposed. The active region of the prominence was AR2407. An individual type III burst was observed at 08:21 UT. The burst lasts for 20 seconds with a drift rate of 4.25 MHz/s. This burst was recorded by the Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy and Transportable Observatory (CALLISTO) at Switzerland. The CALLISTO spectrometer is a spectrometer system that has been installed all around the world to observe the activity of the sun for 24 hours. The activation may be caused by shock waves issuing from prominences and solar flares. The loop prominences can be observed by using the optical telescope and is the initiates points of the following important flare that exist for 6 hours. The active region on the Sun experience the gradual build up of the magnetic field which gives rise to the sunspots, prominences and loops in the corona and produce the powerful outburst explosions.
    Źródło:
    World Scientific News; 2016, 47, 2; 230-240
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The Development of Solar Prominence on 4th September 2015 and the Solar Burst Type III and IV
    Autorzy:
    Norsham, N. A.
    Hamidi, Z. S.
    Mazlan, Muzamir
    Shariff, N. N. M.
    Yusofl, N. S.
    Jafni, A. I.
    Khalib, N. M. F.
    Hamdan, M. N.
    Kamaruddin, Farahana
    Tahar, Muhammad Redzuan
    Monstein, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/1192156.pdf
    Data publikacji:
    2016
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Solar prominences
    active region (AR)
    solar burst
    type III
    type IV
    e CALLISTO
    Opis:
    This article will focus on the solar prominences that occur during the 4th September 2015. On that day, there were two sunspots on the surface of the sun, which were AR2409 and AR2410. These two active regions did not produce any threat for strong flare and thus the solar activity was very low. The prominences that will be focused were both occurred at 0353 UT and 0427 UT respectively. There were minor (G1) geomagnetic storm observed on that day. For solar prominences that occurred at 0353 UT, solar radio burst type (SRBT) IV was detected by CALLISTO spectrometer. From the CALLISTO, two bursts at low intensities with the duration of about 7 minutes for the first burst of 280-320 MHz and 6 minutes for the second burst of 360-430 MHz were observed. For the first burst, energy calculated was between 1.855 x 10 -25 J and 2.12 x 10 -25 J with the drift rate of 0.095 MHz/s. For second burst, the energy obtained was between 2.385 x 10 -25 J and 2.849 x 10 -25 J with the drift rate of 0.194 MHz/s. At 0427 UT, SRBT III was recorded with a frequency of 240-350 MHz with the energy which was obtained between 1.590 x 10 -25 J and 2.319 x 10 -25 J. The drift rate of this type of burst was 0.61 MHz/s. During this event, the solar wind value was 499.3 km/Sec with the proton density of 15.1 protons/cm3.
    Źródło:
    World Scientific News; 2016, 45, 2; 264-275
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-59 z 59

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