Problem 375 - Infinite loop at the bounday of Sphere with multiple scattering of charged particle
Summary: Infinite loop at the bounday of Sphere with multiple scattering of charged pa...
Status: RESOLVED INVALID
Alias: None
Product: Geant4
Classification: Unclassified
Component: geometry/solids (show other problems)
Version: 4.0
Hardware: PC Linux
: P2 normal
Assignee: Vladimir.Grichine
URL: http://www.slac.stanford.edu/~hirofum...
Depends on:
Blocks:
 
Reported: 2002-05-28 13:14 CEST by mizushim
Modified: 2002-05-29 03:49 CEST (History)
2 users (show)

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Description mizushim 2002-05-28 13:14:57 CEST 
Infinite loop (getting in/out of a volume without moving) is found on the
surface of G4Sphare for charged particles with multiple scattering process.
This infinite loop does not occur for neutral particle nor charged geantino.
The sample program, output lists, etc. are posted on
 http://www.slac.stanford.edu/~hirofumi/myprog.html
Comment 1 Vladimir.Grichine 2002-05-29 03:49:59 CEST 
The problem was in the definition of G4Sphere. One should use G4/CLHEP constants
like pi/M_PI rather than fixed values with limited accuracy.

  G4VSolid* spher_solid = new G4Sphere ("ScintiDome",
                                        Rin_spher,
                                        Rin_spher + thick_spher,
                                        0,
					2*pi, //  2*3.1415926535,
                                        0,
                                        2*pi); //  2*3.1415926535);