A distribution associated with the Kontorovich-Lebedev transform

We show that in a sense of distributions [formula], where δ is the Dirac distribution, τ, x ∈ R and Kν(x) is the modified Bessel function. The convergence is in E'(R) for any even varphi(x) ∈ E(R) being a restriction to R of a function varphi(z) analytic in a horizontal open strip Ga = {z ∈ C: |Im z| < a, a > 0} and continuous in the strip closure. Moreover, it satisfles the condition [formula], |Re z| → ∞, α > 1 uniformly in ‾Ga. The result is applied to prove the representation theorem for the inverse Kontorovich-Lebedev transformation on distributions.