$\alpha$-stable processes with $1<\alpha{\leqslant}2$. A series representation of the density of the first hitting time of a point in the case of spectrally positive $\alpha$-stable Lévy processes, $1<\alpha<2$, was obtained in [@Peskir08] and [@Simon11]. That result was extended two general spectrally two-sided $\alpha$-stable processes with $1<\alpha<2$ in [@KKPW14]. Let us note here that in case of spectrally negative Lévy processes starting from the left side of the interval, the first hitting time is equal to the first passage time through the left end and in consequence, one may apply tools from the fluctuation theory to handle the problem (see e.g. [@Bertoin96] or [@Sato99] for details).

The general symmetric case is much harder to handle and in principle, requires some regularity assumptions on the characteristic exponent of the process. In [@MK12spectral] the author derives an integral representation of the distribution function of the first hitting time of a point in terms of eigenfunctions of the semigroup of the process killed upon hitting the origin. That idea was later adopted in [@KJ15] to obtain the asymptotic expansion of the distribution function (and its derivatives) of the first hitting time of a point for symmetric Lévy processes with completely monotone jumps. Recently, in 