TestEm5 for Proton-neutron Reaction

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I am a student and very new to Geant4. I have been asked to simulate protons hitting an iron absorber and neutrons are expected to be generated via the Fe(p,n)Co reaction. The base code used is "TestEm5" under "electromagnetic" extended examples. The main things I modified are:

1. PhysicsList.cc to include all the hadronic processes, such as that of PhysicsList.cc in "hadronic" extended examples.

2. RunAction.cc to include a check and count for neutron particles.

3. Created a .mac file to control the absorber parameters as well as gun particle and energy.

However, in the output:

"
 ======================== run summary ======================

 The run was 10000 proton of 250 MeV through 4 m   of Iron (density: 7.87 g/cm3 )

 Total energy deposit in absorber per event = 249.6 MeV +- 9.381 keV

 -----> Mean dE/dx = 0.6241 MeV/cm      (0.0793 MeV*cm2/g)

 From formulas :
   restricted dEdx = 21.76 MeV/cm       (2.765 MeV*cm2/g)
   full dEdx       = 21.76 MeV/cm       (2.766 MeV*cm2/g)

 Leakage :  primary = 0 eV  +- 0 eV    secondaries = 731 eV  +- 93.51 eV 
 Energy balance :  edep + eleak = 249.6 MeV

 Total track length (charged) in absorber per event = 3.554 cm  +- 3.683 um 
 Total track length (neutral) in absorber per event = 4.885 um  +- 2.539 um

 Number of steps (charged) in absorber per event = 16.25 +- 0.0006069
 Number of steps (neutral) in absorber per event = 0.0034 +- 0.0006069

 Number of secondaries per event : Gammas = 0.0506;   electrons = 203.5;   positrons = 0;   neutrons  = 0

 Number of events with the primary particle transmitted = 0 %
 Number of events with at least  1 particle transmitted (same charge as primary) = 0 %

 Number of events with the primary particle reflected = 0 %
 Number of events with at least  1 particle reflected (same charge as primary) = 0 %
"

Turned out that I did not manage to obtain any neutron particles. I suspect that I did not include an important process. But then again, I practically copied the whole PhysicsList.cc file from the "hadronic" folder.

Your help would be greatly appreciated. I thank you in advance.

Sincerely, Z

   Attachment:
      http://hypernews.slac.stanford.edu/HyperNews/geant4/get/AUX/2009/04/29/13.21-18290-PhysicsList.cc
      http://hypernews.slac.stanford.edu/HyperNews/geant4/get/AUX/2009/04/29/13.21-13884-RunAction.cc