Mathematica tells me the indefinite integral is:
$$ \frac{1}{2} e^{-\frac{\sqrt{\beta ^2}}{2}-\frac{\beta }{2}} \left(e^{\sqrt{\beta ^2}} \left(\text{erf}\left(\frac{1}{2} \sqrt{\alpha } \left(\frac{\sqrt{\beta ^2}}{\alpha }+1\right)\right)-1\right)+\text{erf}\left(\frac{\sqrt{\alpha }}{2}-\frac{\sqrt{\beta ^2}}{2 \sqrt{\alpha }}\right)+1\right) $$
I have tried integration by parts, a few substitutions, to no avail. What trick must I use to integrate this?