TY - JOUR ID - Yakubovich2006 LB - Yakubovich2006 AU - Yakubovich, Semyon B. TI - A distribution associated with the Kontorovich-Lebedev transform ST - A distribution associated with the Kontorovich-Lebedev transform JO - Opuscula Math. JA - Opuscula Math. JF - Opuscula Mathematica PY - 2006 VL - 26 IS - 1 SP - 161 EP - 172 DO - http://dx.doi.org/10.7494/OpMath.2006.26.1.161 UR - http://dx.doi.org/10.7494/OpMath.2006.26.1.161 AB - We show that in a sense of distributions \[\lim_{\varepsilon\to 0+} {1\over \pi^2} \tau\sinh\pi\tau \int_{\varepsilon}^{\infty} K_{i\tau}(y)K_{ix}(y){dy\over y} =\delta(\tau-x),\] where \(\delta\) is the Dirac distribution, \(\tau\), \(x\in\mathbb{R}\) and \(K_{\nu}(x)\) is the modified Bessel function. The convergence is in \(\mathcal{E}^{\prime}(\mathbb{R})\) for any even \(\varphi(x)\in\mathcal{E}(\mathbb{R})\) being a restriction to \(\mathbb{R}\) of a function \(\varphi(z)\) analytic in a horizontal open strip \(G_a=\{z\in\mathbb{C}\colon\,|\text{Im}\,z|\lt a, \ a\gt 0\}\) and continuous in the strip closure. Moreover, it satisfies the condition \(\varphi(z)=O\bigl(|z|^{-\text{Im}\,z-\alpha}e^{-\pi|\text{Re}\,z|/2}\bigr)\), \(|\text{Re}\,z|\to\infty\), \(\alpha\gt 1\) uniformly in \(\overline{G_a}\). The result is applied to prove the representation theorem for the inverse Kontorovich-Lebedev transformation on distributions. KW - Kontorovich-Lebedev transform KW - distributions KW - modified Bessel functions SN - 1232-9274 ER -