[Gate-users] Back to Back source

[Emmanuel BRARD]

Dear All,

I tried once with the two macro commands here-under but I still have some accolinear photon pairs but if I use a modified version of
GateBackToBack.cc in which there is no accolinarity support at all, then everything work well. I would assume that the accolinearity is not correctly supported by this version. I should have a look at how this is implemented for a positron source and copy the implementation for the btb source but I thought maybe this is a known issue by the developers and that It will be fixed in the next release. 

Regards,

--
BRARD Emmanuel 
emmanuel.brard at alumni.u-psud.fr
Medical Physics - PhD Student
IPHC IMABIO Bat 25 - 23 rue du Loess
67037 Strasbourg Cedex 2
FRANCE



-----Message d'origine-----
De : Alexandre Dupas [mailto:alexandre.dupas at gmail.com] 
Envoyé : lundi 21 février 2011 11:57
À : Emmanuel BRARD
Cc : gate-users at lists.opengatecollaboration.org
Objet : Re: [Gate-users] Back to Back source

Dear Emmanuel,

Since, I don't really know what bugs are corrected by the BackToBack.cc you use, I would suggest to try setting the accolinearity to 0 deg and accolinearity flag to false using the following commands:

/gate/source/twogamma/setAccolinearityFlag false /gate/source/twogamma/setAccoValue 0 deg

and looking if the result still contains some accolinear photon pairs.
As I said previously, using Gate v5 (with some patches), we don't have such issues anymore but I cannot say about Gate v6.

Best regards,
Alexandre
--
Alexandre Dupas
Postdoctoral Research Fellow
INSERM U698, CHU X. Bichat, Médecine Nucléaire