I need to simulate interaction of 12C beam (27.5A GeV/c) with 12C target. I tried FTFP_BERT, FTFP_INCLXX, QGSP_INCLXX. The main problem that these physics lists don’t give me heavy fragments of the beam (eg 10B or 11B), only something kicked out of target as it has very small momentum. Can you advice something to try?
please, clarify projectile momentum. Is it really ultra-relativistic ions?
The beam momentum is 13,5A GeV/C (I was wrong before), so for 12C it’s about 165 GeV/c. I used several physics lists and also tried proton target and didn’t have fragment momentum higher than 0.5 GeV, but we’re expecting something about 150 GeV/c (from the actual data). So the question is if it’s possible to find existing physics list to simulate this process.
Recently I was using QGSP_INCLXX physics list to simulate 12C 13.5 AGeV/c on proton target and indeed got fragments with momentum we supposed before. But I tried to calculate fragmentation cross-section, and the value is ten times lower than expected. I’ve read that in new GEANT release there were a new data files for cross-section, could that help the issue? Or maybe still another physics list should be used?
we tried to improve cross sections in Geant4 10.6 but I would not expect a significant difference at this energy. The problem you face may be not only in Geant4 models/x-sections but also in your application, in particular, in normalisation or in method of scoring.
In any case, it would be good to try 10.6. when you try alternative Geant4 Physics Lists you may consider QBBC or QGSP_BIC.