[Gate-users] warning in SPECT simulation

[Didier Benoit]

Hi Saeed,

I've already seen this warning in GATE, it was when I developed my own collimator in GATE. I didn't like this warning, you can have it if the position of your collimator is not good (the collimator in the detector for instance), for me the problem was in the source code, G4double was not enough accurate, I had to use long G4double.

Kind regards,
Didier

On Nov 30, 2011, at 3:26 PM, Saeed Heidary wrote:

> Dear GATE users
> I am using my own changed benchSPECT based on these characteristics ;
> 
> two head and 32 projections ,rotating in 180 deg using a NCAT phantom.
> during the first projection this warning is appeared but GATE is doing
> its progress
> and is not stopped .
> Anybody has encountered such a warning!
> Is it a serious warning and maybe affects the simulation ?
> 
> clearing up the projection data matrices ... done
> WARNING - G4Navigator::ComputeStep()
>          Track stuck, not moving for 10 steps
>          in volume -collimator_phys- at point (171.89,-160.45,-131.711)
>          direction: (0.856014,-0.463663,-0.228597).
>          Potential geometry or navigation problem !
>          Trying pushing it of 1e-07 mm ...
> 
> Many thanks
> _______________________________________________
> Gate-users mailing list
> Gate-users at lists.opengatecollaboration.org
> http://lists.opengatecollaboration.org/mailman/listinfo/gate-users

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Didier BENOIT, GATE Engineer
Imagerie et Modélisation en Neurobiologie et Cancérologie (IMNC)
IMNC – UMR 8165 CNRS – Université Paris 7 – Université Paris 11
Campus d’Orsay
Bâtiment 440
91406 ORSAY Cedex

Tél : (33) 1 69 15 68 76
E-mail : benoit at imnc.in2p3.fr
http://www.imnc.in2p3.fr
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