Proton Calorimetry/Future Work

QuARC Goal

Measure the range of a 250 MeV proton beam with 0.1mm accuracy at 5 kHz, with no transverse position sensitivity in a 30 cm x 40 cm* field. The detector should be nozzle mounted and have all DAQ on board, with 1 power and 1 network connections to the outside world. It should be fully controlled by any web browser, and the GUI should include data review.

*Initially we will stick with a 10 cm x 10 cm field.

Scintillators and PD

• Scintillators uniform in thickness (3mm) and flatness.
• Machine block clear polished sheets.
• For 245 MeV, is it doable to do 1 module of 32 PD with the 2.8mm thick and then 3 modules of 32 PD with scintillators 3mm thick?
• For low energy just 1 module of 2.8mm
• Photodiodes are OK, there are no issues in the coupling.

DAQ & Electronics

Redesign of the analog circuit. The boards need a revision.

• We want everything to connect via usb-C (currently there is only one usb-C cable that does not work properly and it is a very long one). Did Saad discuss this with Marco? What was the outcome of the lab tests?
• We need all the power to come just from FPGA (5V, ~2A) ➾ the voltage regulator chips need to go.
• Long usb-C between the daugther board and the DDC will be removed, and the two can connect directly [daughter board - bridge usb C board - (usb C cable) - bridge board - DDC board]
• FPGA from Saad had some glitches that need to be resolved. Do we see those with Nexus as well as the usb104? ➾ On board fitting needs to be implemented

Calibration and data

Is it possible to calibrate the detector without a proton beam?

• Maybe an e- beam beta source?
• Modify the geant4 simulation to verify what E will we need so there is no quenching?
• Can we obtain average results to mitigate position sensitivity?

GUI

• Implement any options needed that have user input
• Replay and post-processing options
• Version with full live detector control ➾ reset and relaunch options included
• Check current varian control system: what does if offer and how do they control the detector? ➾ Check with Clatterbridge, Allison and A. Mazal

Mechanical design

• For 245 MeV, is it doable to do 1 module of 32 PD with the 2.8mm thick and then 3 modules of 32 PD with scintillators 3mm thick?
• How can we design the modules so they can attach and detach easily? ➾ We need a robust design but not rigid
• Power distribution?
• Beam windows? Light tight?

Future beam tests

• Beam test where we check the shape and position of the BP (scanning field)
• Real treatment plans
• Testing with real gantry mount