[Gate-users] [Gate-devel] Touble with physics in Gate_v6.2 …..

[David Sarrut]

Hello Uwe,

there is a problem with Gate version 6.2 due to a bug in geant4 9.5 : there
is no fluorescence. It may explain the differences.

Didier dig into this and found a workaround but it needs some changes in
Geant4 code (and Gate code), so it cannot by easily corrected now. The bug
has been reported to G4 dev but I don't know yet if geant4 9.6 correct
this.

We need to propose a solution for the next release (at least a short
document explaining changes to be done in G4 code in order for the user to
enable fluorescence).

Sincerely,
David
PS: I put gate-users in copy, because it may be of interest to other users.



On Mon, Mar 18, 2013 at 5:02 PM, Pietrzyk, Uwe <u.pietrzyk at fz-juelich.de>wrote:

>
> Dear Albertine,
>
> in the course of preparing a new example for EduGATE I ran into
> a subtle problem:
> The example refers to Fig. 10-4, p 153 in the book "Physics in Nuclear
> Medicine"
> from Cherry, Sorensen and Phelps, Third Edition, which is nice to explain
> what happens among other things when using NaI(Tl) for gamma
> spectrometry. I succeeded to receive a very similar plot from my
> simplyfied setup as you can see in the attached files. However, the escape
> peak from Iodine is only visible when I run Gate_v6.1 and it is missing
> when I run Gate_v6.2 using the identical macros!
> The Gate_v6.1 result I only got, when I replaced the model from "standard"
> to PenelopeModel, otherwise, the escape peak would not be visible!
> Using the "LivermoreModel" did not change the findings with Gate_v6.2!
>
> Finally, I asked Michaela Gaens to have a quick look into this problem,
> but this seems to be burried into the difference between the two
> GEANT4 versions. This is to difficult for me, hence, I appreciate
> any help. For the moment I'll continue to use 6.1, but it should also
> work for 6.2.
>
> Many thanks and kind regards,
>
> Uwe
>
> PS: Please note, that the example was named "Gamma_Sphere", but in this
> case I replaced the sphere by a plate (1 or two plates).
>
>
> /----------------------------------------------------------------------
> Prof. Dr. Uwe Pietrzyk
> Diplom-Physiker
> Institut für Neurowissenschaften und Medizin / INM-4
> Forschungszentrum Jülich GmbH
> 52425 Jülich
> Tel: +49-2461-61 4763
> Fax: +49-2461-61 2820
> Mobil: +49-162-103-4871
> eMail: U.Pietrzyk at fz-juelich.de
> http://www.fz-juelich.de/inm/inm-4/DE/Home/home_node.html
> &
> Bergische Universität Wuppertal
> Fachbereich C - Physik / D.08.01
> Gaußstr. 20
> 42097 Wuppertal
> Tel: +49-(0)202-439-3523
> Fax: +49-(0)202-439-2811
> eMail: Uwe.Pietrzyk at physik.uni-wuppertal.de
> http://www.medizinphysik.uni-wuppertal.de
> ----------------------------------------------------------------------/
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
> _______________________________________________
> Gate-devel mailing list
> Gate-devel at lists.opengatecollaboration.org
> http://lists.opengatecollaboration.org/mailman/listinfo/gate-devel
>



-- 
David Sarrut, Phd
Chargé de recherche CNRS
CREATIS, UMR CNRS 5220, Inserm U 1044
Centre de lutte contre le cancer Léon Bérard
28 rue Laënnec, 69373 Lyon cedex 08
Tel : 04 78 78 51 51 / 06 74 72 05 42
http://www.creatis.insa-lyon.fr/~dsarrut
_________________________________
 "2 + 2 = 5,  for extremely large values of 2"
_________________________________
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.opengatecollaboration.org/mailman/private/gate-users/attachments/20130320/b4bb96fd/attachment.html>