Question: The solver does not return a result

> restart;
> ode := `assuming`([(diff(r^2*(diff(`ϕ`(r), r)), r))/r^2 = k[0]^2*`ϕ`(r)+Q*Dirac(r)/`ε`[0]], [Q::positive, (`ε`[0])::positive, (k[0])::positive, r::real]);
> ics := `ϕ`(infinity) = 0, `ϕ`(-infinity) = 0;
> dsolve({ics, ode}, `ϕ`(r), method = fourier);

Download pintu.mpl.txt

I have an ODE to solve with boundary condition at +-infinity. (See attachment) The sovler does not return anything. The result is supposed to be Factor*exp(-k_0*r)/r and all the coefficients(factors) should be worked out. What is wrong? Thank you in advance.

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