Trouble generating particles above 26 MeV?

Hi all,

So I’ve been running simulations successfully using a GPS macro file for the last while. Energies have only needed to go up to about 25 MeV. I’m using a custom geometry mod of exampleB1 to run everything.

I wish to run a mu- simulation with a monoenergetic source of 4000MeV. When I do this, my run starts to loop, and doesnt generate particles properly. I’ve checked the, …etc files and everything seems to check out.

I’ve flip flopped my physics lists a bunch. I was using Shielding.hh, and have switched to FTFP_BERT and none of them seem to alleviate the problem.

I narrowed it down to it not generating particles above 26 MeV after some finagling, and just continually looping and freezing.

Anyone know where/what to check/what could cause this?

I can post all my files at your request.

Please help :(. I am in dire dire need. I’ll try and make a video file of what its doing, but its basically just frozen off of the first particle as soon as the energy gets above that threshold.