Results interpretation of USRYIELD

Dear FLUKA experts,

Recently I am using USRYIELD to score the photon spectrum from 10 keV electrons on copper. The scoring was taken in energy in 400 bins from 0 to 10 keV, and polar angle from 130 to 140 degrees with reference to the electron direction. So the solid angle in detected area should be about 0.75 steradian. However, in the results (attached figure and .lis file) there seems to be problems in the energy balance. For the results, taking as in per steradian in the detected area of [130, 140] degrees, only with photons with energy of 5 keV, with a count in the results of about 5, in 0.75 steradian, the total energy is already larger than the primary electron.

Will you please take a look to see, whether the problem is from the model or my understanding in the results of the detector?

Thanks for your help!

D11-10.inp (1.5 KB)
USR-1D D11-10 23
D11-10_23_tab.lis (23.9 KB)

Dear Yu Xiao,

the values in a .lis file of an USRYIELD detector are double differential ones. This means in your case the unit of these values should be: 1/[Kinetic Energy]/[Solid angle]/primary = 1/GeV/sr/primary

The detailed information of the scoring is available in the .sum file.


Dear Dávid Horváth,

I get it. The omitted GeV in the denominator makes the integration of the results sound in dimensionality.

Thanks a million!