I need to solve this Fredholm integral equation of the second kind:
The kernel is:
where a: real, i: imaginary unit.
I tried to solve this with the method described here: Integral equation numerical solution with NDSolve, this is the best algorithm for this case I have come across so far but it takes for ages and in the end it doesn't produce any result (due to memory insufficiency). Could anyone please help me solve it?