Problem 1695 - Time of Products from Nuclear Muon Capture are too short
Summary: Time of Products from Nuclear Muon Capture are too short
Status: RESOLVED FIXED
Alias: None
Product: Geant4
Classification: Unclassified
Component: processes/hadronic/stopping (show other problems)
Version: 10.0
Hardware: PC Linux
: P5 major
Assignee: Vladimir.Ivantchenko
URL:
Depends on:
Blocks:
 
Reported: 2014-12-01 19:50 CET by a.edmonds
Modified: 2014-12-13 03:07 CET (History)
0 users

See Also:

Attachments
Plot of proton arrival times from nuclear muon capture on aluminium (10.24 KB, image/png)
2014-12-01 19:50 CET, a.edmonds 		Details
Plot of proton arrival times from nuclear muon capture on aluminium (after patch) (10.72 KB, image/png)
2014-12-02 10:56 CET, a.edmonds 		Details
Patch to fix the time of nuclear capture products (10.03 KB, patch)
2014-12-02 10:56 CET, a.edmonds 		Details | Diff
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Description a.edmonds 2014-12-01 19:50:09 CET 
Created attachment 297 [details]
Plot of proton arrival times from nuclear muon capture on aluminium

Hi

I'm having problems with the timing of products from nuclear muon capture in Geant4.10.00.p02.

My simulation fires muons at an aluminum target and there is a sensitive detector volume separately that records anything emitted from it. However, the global arrival time of these protons is much too short when compared to the muonic atom lifetime (864ns). I've attached a plot to show the actual arrival times.

I'm using physics list QGSP_BERT.hh, which uses G4StoppingPhysics which then uses G4MuonMinusCapture.

From a little bit of debugging myself it seems that the random time generated by G4MuonMinusCapture is not used for the nuclear cascade but is used for the decay.
Comment 1 a.edmonds 2014-12-02 10:55:44 CET 
Hi

So, Vladimir Ivantchenko has provided me a patch for this. I've attached both the patch and a plot showing that arrival times are closer to what we expect.

Many thanks
Andy
Comment 2 a.edmonds 2014-12-02 10:56:12 CET 
Created attachment 298 [details]
Plot of proton arrival times from nuclear muon capture on aluminium (after patch)
Comment 3 a.edmonds 2014-12-02 10:56:58 CET 
Created attachment 299 [details]
Patch to fix the time of nuclear capture products