Problem 1223

Summary:	57Co second transition treatment in G4NuclearDecayChannel
Product:	Geant4	Reporter:	Ko Abe <abe>
Component:	processes/hadronic/models/de_excitation/photon_evaporation	Assignee:	dennis.herbert.wright
Status:	RESOLVED FIXED
Severity:	minor
Priority:	P5
Version:	9.4
Hardware:	All
OS:	All

Description Ko Abe 2011-06-22 14:08:23 CEST

Dear All,

I am trying to simulate 57Co decay in liquid scintillator.
In previous geant4.9.3, most event have proper total energy deposit of 136 keV.
While in geant4.9.4.p01, it becomes ~129keV.

In most case 57Co decays to excited 57Fe[136.5], then transit to 57Fe[14.4] with emission of 122keV gamma, and with another transition it reaches to stable.
In geant4.9.3, these consecutive processes are treated in one step with G4PhotoEvaporation::BreakItUp called by G4NuclearDecayChannel.cc.

From geant4.9.4.p01, the two transition processes are separated.
First transition looks treated properly.
G4PhotoEvapoartion::BreakUp treates this and generate daughter nuclei of 57Fe[14.4] for a next step.
But it looks that this second transition of 57Fe[14.4] is not processed.
Following is error message from program.
"G4RadioactiveDecay::DecayIt: Fe57[14.4] is not a valid nucleus for the RDM".

Is this because G4RadioactiveDecay cannot process Fe57 transition due to no existence of RadioactiveDecay3.3/z26.a57?
Can same situation be happen for other radio active nuclei which decays to nuclei whose data is not exist in RadioactiveDecay?

Comment 1 dennis.herbert.wright 2011-09-09 23:36:41 CEST

You are correct.  If the isotope or isomer does not exist, the decay chain stops.
This is the case for any isotope missing from the database.
Our data entries come from ENSDF, and if there are no or very few data there, we do not include the isotope.   However, if you have data (for 57Fe for example) you could send it us and we can make an entry in our database.