About the scatter correction in using GATERootToCastor function

Dear CASToR users and developers,

The scatter correction is not applied when converting GATE simulation data (GATERootTocastor) using the TOF option in version 3. But, it is possible in version 2.
Q1. I want to apply a scatter correction when converting the GATE data (list mode) using the TOF option. If so, is it correct to use version 2?

Q2. Confirmed that the bugs in version 2 were fixed in version 3. Can I still use version 2?
I wonder if there is no difference (version2 vs version 3) in TOF reconstruction using list-mode data.

Thanking you in advance for your responses,

Sincerely,

Hi,

This option has been removed from version 3 as the scatter rate computation (directly calculated from the root metadata) is not consistent with TOF data as it doesn’t take into account the TOF bin size, thus the implementation in version 2 was incorrect.

Besides, this option does not really provide a scatter correction estimation, but the actual rates directly computed from the Monte-Carlo simulated data. Currently there is only the possibility to ignore scatter/random events in the resulting datafile using the -t option, otherwise the scatter correction factors estimation must be preformed and implemented by the user.

You can have more details regarding scatter correction with TOF in the following discussion thread: https://lists.castor-project.org/pipermail/castor-users/2019-November/000281.html

Kind regards,
Thibaut