Add Hypernuclei and Open Charm decay

requested review from @v.friese

assigned to @v.friese

added 1 commit

• db3a3e3d - Add Hypernuclei and Open Charm decay

Compare with previous version

Dear @f.uhlig, @v.friese, @p.-a.loizeau,

you have been identified as code owner of at least one file which was changed with this merge request.

Please check the changes and approve them or request changes.

added CodeOwners label

@i.vassiliev,

could you please rebase the MR locally since it can't be done from the web interface.

added 132 commits

• db3a3e3d...119d9884 - 130 commits from branch computing:master
• d87d6f4b - Add Hypernuclei and Open Charm decay
• 8ae0cb7d - Add Hypernuclei and Open Charm decay

Compare with previous version

I am sorry for attending to this only now.

This is but a patch, and I am not really fond of it, for several reasons:

1. The whole thing will not work with Geant4, since the method PiAndEtaDecay does nothing in that case.
2. The definition of the additional particles (hyper-nuclei) is misplaced in this method. It should rather be in RegisterIons. However, there it is added to the TDatabasePDG instance; I am not really sure whether that means that the transport engine knows about it. It seems to work, though, for non-strange ions.
3. The choice of the PDG code for the hypernuclei does not follow the PDG Monte-Carlo numbering scheme. According to that, the PDG code for e.g. 3_Lambda_Helium would be 1010020030.

@f.uhlig Do you know what the proper way is to get user-defined decays into TGeant4?

added Simulation label

Discussion in Physics Board of 4 April 2025: Keep this as preliminary solution for the current data production; do the proper implementation for the next release May25. It appears that the method PiAndEtaDecay (TVirtualMC::SetDecayMode()) meanwhile works also for Geant4.

So I merge this now, making a Redmine issue (#3603) in order not to forget the proper implementation.

approved this merge request

@i.vassiliev Please rebase, I cannot do that from here for some reason.

resolved all threads