[Gate-users] How to measure the X-rays scattered by the phantom when they enter the detector?

[David Leibold]

Dear Masa,

May I summarise your requirements:

1) You mention that you want to simulate a CsI detector, but with 100 % detection efficiency and no interaction within the detector.

2) You would like to distinguish between scattered and primary rays.

3) A monochromatic pencil beam enters a phantom.


My suggestion:

I would suggest using a phase space actor (see the documentation here<https://opengate.readthedocs.io/en/latest/tools_to_interact_with_the_simulation_actors.html#phase-space-actor>), which registers each particle's energy, position, velocity etc. crossing its surface. Since you do not want to simulate interaction in your CsI detector material, there is no need to use it in the first place.

Since you are using a pencil beam, all primary photons will go straight through your phantom, intersecting your detector at, for example, point (0,0). All scattered radiation will intersect your detector away from point (0,0). Hence, you can filter out the scatter and primary rays purely based on where they end up on your detector.

To set up your detector, use e.g. a box volume with the desired size, fill it with vacuum, and attach a phase space actor to it.

If you need more help, please let us know.

Best regards,
David



On 30 Aug2022, at 00:46, mas <fight1_fight2 at yahoo.co.jp<mailto:fight1_fight2 at yahoo.co.jp>> wrote:


Hi GATE users.
I am masa at japan and new to Gate.

I am currently working on a simple simulation.
I am trying to find the point spread function of the scattered rays detected by a CsI detector by injecting a pencil beam of monochromatic X-rays into an acrylic phantom.

Assuming a detector detection efficiency of 100%, I want to output the spread of scattered radiation when it enters the detector.
No interaction occurs with the detector.　I also want to output scattered rays and primary rays separately.
How should I set up the detector in such a case?

Should I use Fluence Actor for detection?
Or should I use a sensitive detector?

I would appreciate it if you could help me.

Thank you.

_______________________________________________
Gate-users mailing list
Gate-users at lists.opengatecollaboration.org<mailto:Gate-users at lists.opengatecollaboration.org>
https://urldefense.com/v3/__http://lists.opengatecollaboration.org/mailman/listinfo/gate-users__;!!PAKc-5URQlI!5R6DdcwuD-nXX0bmvN3RckxZ2HEAgen9ExhbGuDcz_52hS9V1Rohx8vBP7HBR0msh9Bx0lNmj5dJ866ftlukHHjC8jk0_A$

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.opengatecollaboration.org/pipermail/gate-users/attachments/20220901/a25e4707/attachment.html>