Neutron capture process not working?

Hello all,

I’m currently working on a simulation where a mercury cylinder is struck by 1 GeV proton beam, which creates multiple neutrons. The mercury cylinder is surrounded by a sensitive detector which detects neutrons. The neutrons then go through the sensitive detector and hit an Li-6 cylinder which surrounds the neutron sensitive detector and the mercury cylinder. The idea is that we should see some events of neutron capture resulting in the creation of alpha particles. Also, surrounding this entire simulation is another sensitive detector cylinder, which detects alphas.

However, I cannot detect any alpha particles and looking at the visualization, I can see that no alpha particles are being generated, even though neutrons are indeed passing through the Li-6 geometry. The energy of the neutrons have no impact; I’ve tried neutrons in all energy ranges and I still can’t seem to generate the Li-6 neutron capture process.

I’ve included my file with all my physics processes. I’ve included redundant and exhaustive physics processes in an attempt to see if I was missing any processes. I’m also including my where all materials and geometries are created.

Please let me know if any other files are needed.

I thank you all for your help and sorry if I missed anything obvious! (2.6 KB) (6.8 KB)

Here, a run of example Hadr03 with QGSP_BIC_HP selected (see

aakas.mac.txt (380 Bytes)
aakas.out.txt (1.3 KB)