[Gate-users] Error true coincidence?

[jinxia guo]

Dear GATE group and users,

I found a question when I simulated PET system.The PET system is consisted
of 24 crystals(See attached picture and mac file). The radial is 40.0164mm
and the crystal size is 2.62mm * 2.62mm * 3mm. I set a point
source(twogamma,backtoback) in the centre of the system.In the simulated
result,the LOR of some true coincidences can't go through the positon of the
source. An example is as follows:
eventID       rsectorID   primaryID           time
PosX             PosY            PosZ           localPosX
localPosY       localPosZ      edep           processname
18100722        9             2        4.89282814465004719295393e+02
-29.673380    28.104630    -0.181436    -0.661178    1.109273
-0.181436      1.553e-01      compt
18100722        5             0        4.89282814465209696663806e+02
10.451629    39.452168    0.000000    -0.703453    0.115474    0.399466
1.799e-01       phot

Could anyone know the reason? Thank you very much for your help.

Regards,
JinxiaGuo

-- 
Jinxia Guo
School of Life Sci&Tech
D11 Building Room 503
Huazhong Univ. of Sci. & Tech
1037 Luoyu Road, Wuhan 430074, China
Tel:+86-27-8779-2294
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