Neutron source in water

Source Definition
1

Dear FLUKA experts,
I am trying to define a simple neutron source in water using the old source routine,
but I get the error “Program received signal SIGFPE: Floating-point exception - erroneous arithmetic operation”.
When I switch the surrounding material to Lead or switches off the source routine the error does not appear.
What should I add to the source routine?
Please refer to the attached files.

Thank you in advance,
neutrontry.flair (1.7 KB)
neutrontry.inp (1.1 KB)
source.f (9.0 KB)

Hen Shukrun.

2

Hi Rachel,

In your source you specify:

*  |  Kinetic energy of the particle (GeV)
         TKEFLK (NPFLKA) = 1.0D-3
*         TKEFLK (NPFLKA) = SQRT ( PBEAM**2 + AM (IONID)**2 )
*     &                   - AM (IONID)
*  |  Particle momentum
         PMOFLK (NPFLKA) = PBEAM

The two instructions are incompatible: in your input file you specify a 2 MeV neutron energy. Therefore, you need to decide where you set the energy. Assuming you want to set it in the source file, you need to write the following:

*  |  Particle momentum
*         PMOFLK (NPFLKA) = PBEAM
         PMOFLK (NPFLKA) = SQRT ( TKEFLK (NPFLKA) * ( TKEFLK (NPFLKA)
     &                          + TWOTWO * AM (IONID) ) )

Cheers,
Daniele