[Gate-users] Ion source - timestamp problem GATE 6.1

[STRYDHORST Jared]

I just compiled GATE with the release version of G4 10.2 and the problem seems to have gone away. Maybe something has changed so the SetPDGLifeTime() works again.

Jared STRYDHORST

Laboratoire Imagerie Moléculaire In Vivo (IMIV)
UMR 1023 Inserm/CEA/Université Paris Sud - ERL 9218 CNRS
CEA/I2BM/Service Hospitalier Frédéric Joliot
4, place du Général Leclerc
91401 ORSAY Cedex

http://i2bm.cea.fr/dsv/i2bm/shfj/imiv

________________________________________
De : gate-users-bounces at lists.opengatecollaboration.org [gate-users-bounces at lists.opengatecollaboration.org] de la part de Gergely Patay [gergely.patay at mediso.com]
Envoyé : mercredi 13 janvier 2016 09:42
À : gate-users at lists.opengatecollaboration.org
Objet : Re: [Gate-users] Ion source - timestamp problem GATE 6.1

Dear Enrique,

the ion timestamp problem is caused by a protected (i.e. non user-settable)
"isGeneralIon" field in the Geant4 G4ParticleDefinition class (for the details,
see
http://lists.opengatecollaboration.org/mailman/private/gate-users/2015-April/008344.html
) .

A minimal workaround might be as follows :

1) change visibility of isGeneralIon from protected to public:
geant4/particles/management/include/G4ParticleDefinition.hh:402
-   protected:
+   public:
        G4bool isGeneralIon;

(this might be modified *without* recompiling Geant4)

2) add the following line to gate/source/physics/src/GateVSource.cc:269
           GetParticleDefinition()->SetPDGLifeTime(0);
+         GetParticleDefinition()->isGeneralIon=false;

3) recompile Gate with the modified header file.

Since it requires to modify a file *outside* of the Gate source tree, I'm not
sure how to do it automatically.

best regards,
  Gergely

--
Gergely Patay
Mediso Ltd.


On 2016-01-12 18:09, Enrique Muñoz Albaladejo wrote:
> Thank you very much for your response, the problem seems to be exactly as you
> describe it. It looks like it ignores any time settings I define and takes the
> time of the simulation to be that which makes the source run out of activity.
>
> I have encountered this problem when simulating a Na22 source with GATE 7.1 and
> geant4.10.01.p02, and a colleague of mine has the same problem with GATE 6.1 and
> Geant4 9.4 (she wanted to simulate 176 Lutetium).
>
> I tried to read through the Geant4 code and I can't figure out why the function
> SetPDGLifeTime() would ignore the attempt to modify the lifetime of an ion, but
> my programming knowledge isn't that deep.
>
> Thanks again.
>
> Enrique Muñoz
>
> On 04/01/16 09:37, STRYDHORST Jared wrote:
>> What version of GATE and Geant4 are you using and what ion?
>> GATE schedules the decay of ions itself according to the activity set by the
>> user. To do so, it calls a function that sets the lifetime of the ion in
>> Geant4 to zero so it decays immediately when it's created. However, in version
>> 10 (.1?, .2? I don't know exactly when the change was made.) of Geant4, the
>> function (SetPDGLifeTime()) now ignores any attempts to modify the lifetime of
>> an ion. So the ion is created by GATE, but then Geant4 calculates the decay
>> time according to the real half-life of the ion.
>>
>> Jared STRYDHORST
>>
>> Laboratoire Imagerie Moléculaire In Vivo (IMIV)
>> UMR 1023 Inserm/CEA/Université Paris Sud - ERL 9218 CNRS
>> CEA/I2BM/Service Hospitalier Frédéric Joliot
>> 4, place du Général Leclerc
>> 91401 ORSAY Cedex
>>
>> <mailto:karima.ait-aissa at cea.fr>
>> <http://i2bm.cea.fr/dsv/i2bm/shfj/imiv>http://i2bm.cea.fr/dsv/i2bm/shfj/imiv
>> --------------------------------------------------------------------------------
>> *De :* gate-users-bounces at lists.opengatecollaboration.org
>> [gate-users-bounces at lists.opengatecollaboration.org] de la part de Enrique
>> Muñoz Albaladejo [Enrique.Munoz at ific.uv.es]
>> *Envoyé :* lundi 21 décembre 2015 12:32
>> *À :* gate-users at lists.opengatecollaboration.org
>> *Objet :* [Gate-users] Ion source - timestamp problem GATE 6.1
>>
>> Dear all,
>>
>>
>> I am trying to use an ion source for a PETscanner.
>>
>> The simulation provides strange values for the time stamp of the singles.
>> The parameter  "setTimeStop"  was set to 50s, but the timestamp of the first
>> detected single was 3.4x10^17 s.
>>
>> I would like to know if there is any solution to this problem.
>>
>> Best regards,
>>
>> Enrique
>
>
>
> _______________________________________________
> Gate-users mailing list
> Gate-users at lists.opengatecollaboration.org
> http://lists.opengatecollaboration.org/mailman/listinfo/gate-users
>
_______________________________________________
Gate-users mailing list
Gate-users at lists.opengatecollaboration.org
http://lists.opengatecollaboration.org/mailman/listinfo/gate-users