Problem 2088 - wrong proton momentum in G4NeutronBetaDecayChannel
Summary: wrong proton momentum in G4NeutronBetaDecayChannel
Status: RESOLVED FIXED
Alias: None
Product: Geant4
Classification: Unclassified
Component: particles (show other problems)
Version: 10.4
Hardware: All All
: P4 minor
Assignee: kurasige
URL:
Depends on:
Blocks:
 
Reported: 2018-09-07 04:26 CEST by ichikawa
Modified: 2018-09-07 06:15 CEST (History)
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Description ichikawa 2018-09-07 04:26:24 CEST 
Dear Geant4 team,

in G4NeutronBetaDecayChannel::DecayIt(G4double), decay product proton momentum is fixed to 1 and its direction is not rotated by a rotation matrix, then the energy momentum is not conserved.

I think that the correction is as follows:

in G4NeutronBetaDecayChannel.cc
after line 218 just after defining direction2:
->              direction2 = rm * direction2;

line 220: = new G4DynamicParticle( G4MT_daughters[2], direction2);
->        = new G4DynamicParticle( G4MT_daughters[2], direction2*pP);


Best regards,
Go
Comment 1 kurasige 2018-09-07 06:15:13 CEST 
Thank you very much for reporting the bug.

The fixed version will be included in the next release (and patches)