Consider the function $f(x)=\frac{1}{\sqrt{2 \pi} s |x|} e^{-\frac{(a x +b )^2}{2 (s x)^2}}$, where $s>0$. I am interested in the convolution of $f$ with the Gaussian kernel $g(x)=\frac{1}{\sqrt{2 \pi}}e^{-\frac{x^2}{2}}$. Let's refer to this convolution as $h(x)$,
$h(x)=\int_\mathbb{R} g(x-t) \, f(t) \, dt$.
I first tried to obtain a closed form expression for $h(x)$, but I failed. So my next goal is find an approximation to $h(x)$. However, that turns out to be challenging too. I appreciate any idea how to obtain an "analytical" approximation to $h(x)$.
Best
Golabi