2004 – Crash During Heavy Ion Simulations with GPS

Problem 2004 - Crash During Heavy Ion Simulations with GPS

Summary: Crash During Heavy Ion Simulations with GPS

Status:	RESOLVED FIXED

Alias:	None

Product:	Geant4
Classification:	Unclassified
Component:	processes/hadronic (show other problems)
Version:	other
Hardware:	All Linux

Importance:	P4 major
Assignee:	Vladimir.Ivantchenko

URL:

Depends on:
Blocks:

Reported:	2017-09-10 04:50 CEST by Matthew Lund
Modified:	2018-08-14 10:42 CEST (History)
CC List:	3 users (show)

See Also:

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Description Matthew Lund 2017-09-10 04:50:55 CEST

When running large simulations with heavy ions generated from GPS, GEANT4 keeps crashing with the following error message. Using GEANT4.10.04.b01 currently with crash.

-------- EEEE ------- G4Exception-START -------- EEEE -------
*** G4Exception : DECAY003
      issued by : G4Decay::DoIt
Can not determine decay channel for neutron
  mass of dynamic particle: 0.930611 (GEV)
  dacay table has 1 entries
0: BR 1, IsOK? 0, --> e- + anti_nu_e + proton

*** Fatal Exception *** core dump ***
-------- EEEE -------- G4Exception-END --------- EEEE -------

Comment 1 kurasige 2017-09-20 05:24:12 CEST

Hi, Matthew

 Could you let me know the physics list you use ?
 
 I tried to reproduce the problem with example/basic/B3 on GEANT4.10.04.b01. But, I found that neutron can decay successfully.

Cheers,
           Hisaya

Comment 2 Matthew Lund 2017-10-09 17:39:27 CEST

I had the problem using the QBBC physics list. Iron nuclei, Carbon, Boron, Oxygen nuclei with a Galactic Cosmic Ray spectrum have all given me the error. I have tried manually setting the decay to the only one mode with 100% branching ratio, still have the error.

Comment 3 kurasige 2017-10-11 11:16:38 CEST

Hi, Matthew 

 I found the origin of the problem.
 The problem comes not from 'decay channel' but from 'mass' of neutron.
 The error message says that dynamical mass of neutron is 0.930611 GeV. It is bigger than proton mass. So, this neutron can not decay at all.
 This dynamical mass of neutron is set by hadronic processes as a result of interaction of ions. 
 I'll forward this problem to the coordinator of hadronic processes

Cheers,
            Hisaya

Comment 4 kurasige 2017-10-11 11:33:18 CEST

Soory for typo

 The error message says that dynamical mass of neutron is 0.930611 GeV. It is lighter than proton mass. So, this neutron can not decay at all.
 
                            Hisaya

Comment 5 dennis.herbert.wright 2017-10-26 18:40:50 CEST

This could be the binary cascade model in QBBC.   It uses dynamical masses. Referring this to Vladimir, but maybe Gunter should handle it.

Comment 6 Vladimir.Ivantchenko 2017-12-12 21:55:22 CET

Hello,

I have tried to reproduce the problem using Geant4 10.4 in B3a but do not see this problem. It is needed to attach macro file to this bug report and specify if B3a or B3b example is used.

The bug may exist or not in 10.4 but I am sure, that special conditions should be created in order to reproduce.

VI

Comment 7 Vladimir.Ivantchenko 2018-07-06 09:33:36 CEST

Hello,

we cannot reproduce the problem with 10.4 release. Is the bug still exist? What macro to use?

VI

Comment 8 Vladimir.Ivantchenko 2018-08-14 10:42:19 CEST

Hello,

I expect, that the problem disappears in Geant4 10.4, so we close this problem report and a new one will be reopened if it will appear again.

VI