Problem 464

Summary:	compton scattering angular distribution of polarized photon
Product:	Geant4	Reporter:	mizuno
Component:	processes/electromagnetic/lowenergy	Assignee:	longof
Status:	RESOLVED DUPLICATE
Severity:	normal
Priority:	P2
Version:	4.0
Hardware:	PC
OS:	Linux
URL:	http://www.slac.stanford.edu/~mizuno/G4Polarimeter/

Description mizuno 2003-02-27 19:12:01 CET

We have construct a detector simulator for polarized X-ray detector and found a
possible minor bug in low energy physics process. We have constructed plastic
scintillator slab of 20cm thickness and shot 100keV X-rays whose polarization
vector is (1, 0, 0) along z-axis. We saw azimuth angle asymmetry for the first
compton scattered photons (that is good), but couldn't see any asymmetry for
the second or latter ones. We appreciate if you could examine this issue. For
reference, you can get two figures from
http://www.slac.stanford.edu/~mizuno/G4Polarimeter/. The one (p1.gif) is the
azimuth angle dependence of the first scattered photons, and the other (p2.gif)
for the second scattered photons. We are using Geant4 4.0 with patch2.

Comment 1 pia 2003-02-28 00:22:59 CET

Thanks for your information. The problem report is reassigned to the author of
the G4LowEnergyPolarizedCompton class, who will contact you as soon as possible
with further information.
Best regrads,
Maria Grazia Pia

Comment 2 francesco.longo 2003-05-27 10:45:59 CEST

We tested the angular distribution of a double compton event both using a simple
unit test and a full detector simulation and found that the double compton
azimuthal distribution for a lineraly polarized incident photon is well reproduced.
F.Longo and G.Depaola

Comment 3 francesco.longo 2003-05-27 11:15:59 CEST

Some other tests are required to solve the bug. F.Longo and G.Depaola

Comment 4 Gabriele Cosmo 2004-02-18 01:31:59 CET

*** This bug has been marked as a duplicate of 578 ***
*** 'longof@ts.infn.it' will be responsible for this bug. ***