1. The problem statement, all variables and given/known data Electric field for a single pulse of a laser (operating at central wavelength of 800nm): Code (Text): E = E0e^(-(t^2/2a^2))e^(iwt) (the a is sigma and w is omega) Derive an expression for the spectral intensity (irradiance) 3. The attempt at a solution One way I know to calculate irradiance is the time average of the poynting vector: (1/u0)*ExB But that would involve taking the time average of e^(-(t^2)) which is non-integrable. I've also seen the function E integrated over an area, then squared to give an irradiance formula, but then again I run into problems with that function that's difficult to integrate. Any suggestions?