Hi MANG2004, peu9Bgs
:0:Tl/))
I am curious about your calculation, too. Plus, the definition of σ refers to 1/e^2 width not the FWHM. Even your calculation/defintion is correct. I have a doubt that it will work when the specualr incident ray angle is not normal......... C0[U}Y/r2
'UhHcMh:
For thsoe who knows it better, please have some input. I am rather curious, too!! Thanks!!