How to obtain the energy spectra of photon/neutron by USRBDX

Dear experts,
I am trying to calculate the energy spectra of photon and neutron produced by the reaction: 3MeV proton beam hit the copper target.
I tried to use USRBDX, but the results from “_sum.lis” files all were zero.
I am not sure where the problem lies, kindly give me some suggestions.
Cu3MeV-0.1cm.flair (4.7 KB)
Cu3MeV-0.1cm.inp (3.2 KB)
Cu3MeV-0.1cm_21_sum.lis (102.3 KB)
Cu3MeV-0.1cm_22_sum.lis (102.3 KB)
Cu3MeV-0.1cm_31_sum.lis (102.3 KB)

Thank you so much for your help in advance!
Cu3MeV-0.1cm_32_sum.lis (102.3 KB)

You talk about copper, but actually you implemented a tantalum target, where no reaction can take place (and so no secondary particle can be produced) being the proton energy below the Coulomb barrier. On the other hand, reactions can take place in copper, but their probability is extremely low, since the proton range is only of the order of several tens of microns (so most protons stop rather than undergoing a nuclear reaction). Therefore, once you move to copper, you will need a LAM-BIAS card to bias the reaction occurrence.

Dear Francesco,
First of all, thank you very much for your reminder.
Then, how do I set those parameters on the LAM-BIAS card?
I have tried to search for the excitation functions of neutrons and photons produced by the reaction between protons and copper, but have not found them. I would greatly appreciate it if you could provide a search method for the excitation function (such as website links, etc.)!

You shall look at the value of the inelastic scattering length for PROTON at beam energy in the material table of the output file, and divide the aforementioned proton range by the latter (unless it’s infinite, i.e. of the order of 1E30 cm, meaning that no reaction can take place), so as to get an estimate of the required biasing factor to be input in WHAT(2).
An useful website for (available) reaction data is EXFOR.