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<span style="background: transparent; margin-top:0pt; margin-bottom:0pt" data-preserver-spaces="true">Dear CASToR users,</span></p>
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<span style="background: transparent; margin-top:0pt; margin-bottom:0pt" data-preserver-spaces="true">I am simulating a TOF PET scanner in GATE, and I would like to reconstruct an image with scatter and random correction. I am using "castor-GATErootToCastor"
utility function, and I noticed an option "-src" that computes scatter and random correction rates for each LOR. Performing a test, I noticed this option reconstructs basically the same image as if only true coincidences (option "-t") are reconstructed. I
presume the function calculates exact correction factors and thus no statistical (Poisson) noise is introduced into the image. To introduce this statistical noise that is inevitable in real world, my idea is to obtain correction factors from one simulation
and then use them to reconstruct an image from a separate simulation (same simulation but with a different seed). My questions are:</span></p>
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<li style="background: transparent; margin-top:0pt; margin-bottom:0pt"><span style="background: transparent; margin-top:0pt; margin-bottom:0pt" data-preserver-spaces="true">Is there an option to extract just the scatter and correction factors from the simulation?</span></li><li style="background: transparent; margin-top:0pt; margin-bottom:0pt"><span style="background: transparent; margin-top:0pt; margin-bottom:0pt" data-preserver-spaces="true">Is there a simple way to include correction factors into list-mode data (I want to include
TOF information)?</span></li><li style="background: transparent; margin-top:0pt; margin-bottom:0pt"><span style="background: transparent; margin-top:0pt; margin-bottom:0pt" data-preserver-spaces="true">Any other experience/suggestion how to perform scatter and random correction? Maybe
it is better/easier to modify "castor-GATERootToCastor" function and introduce some statistical noise when determining correction factors.<br>
</span></li></ul>
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<span style="background: transparent; margin-top:0pt; margin-bottom:0pt" data-preserver-spaces="true">Any advice and suggestion will be greatly appreciated. Thank you!</span></p>
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<span style="background: transparent; margin-top:0pt; margin-bottom:0pt" data-preserver-spaces="true">Best Regards,</span></p>
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<span style="background: transparent; margin-top:0pt; margin-bottom:0pt" data-preserver-spaces="true">Gasper</span></p>
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<span style="background: transparent; margin-top:0pt; margin-bottom:0pt" data-preserver-spaces="true">(PhD student)</span></p>
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