Proton Calorimetry/Experimental Runs/2021/Nov2

Afternoon test at UCLH with photodiodes and CMOS sesnor.

Experiment Equipment

Item	Notes
Network Hub	Set in control room to take output from experimental room ethernet connection. Control laptops connected via 5GHz WiFi.
Control Laptop x2	1 for remote control for sensor and FPGA, 1 for notes/web GUI.
Ethernet Cable x 3	To connect DAQ laptops to network in the experimental room, network hub to network in control room.
Portable Enclosure	Modified Big Zarges Waterproof Wheeled Equipment Case. Features mount for scintillator stack, front and back openings for beam, patch panel with ports for SHV, BNC, SMA, USB, Camera Link cables. Hole for sensor powering. Mylar windows with Al support mounted to internal face: approximately light-tight.
Scintillator stack	X x 10 mm, Y x 10 mm and Z x (approx) 2.8 mm sheets in ascending order from the front/beam of the end of the scintillator. Sheet numbers from front to end (in beam direction): . Full stack thickness measurements (in mm): .
Nikon D7500	Connected to DAQ Laptop via USB cable.
DAQ laptop x1	Control sensor and photodiode acquisition.
Nexys Video FPGA development board.	For interfacing between DDC232 and PC.
Rev. 2 Texas Instruments DDC232 custom circuit board (x2)	Each housing 16x Hamamatsu S12915-16R photodiodes, coupled directly to scintillator sheets with optical gel. Aligned by eye to scintillator sheets.
Gloves	For handling scintillator
Optical Gel	For photodiode-scintillator optical coupling

Schematic

DDC232 Instructions

• Bash script prog.sh executes FTDI.cpp and livePlot.cpp. Execute with . prog.sh 2 350 0 170 0 50 true 20211102/capture.txt in the directory Photodiodes.
  • First argument is the number of DDC232s.
  • Second argument is the full-scale range (FSR) in pC. Choices are: 12.5, 50, 100, 150, 200, 250, 300, 350.
  • Third argument is the y-scale for the ROOT display. Set to 0 for default.
  • Fourth argument is the integration time in us. Range is 170-1455. Set in multiples of 5 us.
  • Fifth argument is the number of measurements to acquire. Typically acquire 5700 measurements per second. Set to 0 for infinite loop.
  • Sixth argument is the rate in Hz to update the file average.csv for ROOT/web GUI plotting.
  • Seventh argument is a boolean to choose whether to display the ROOT plot.
  • Eighth argument is the filename and destination for the output hexadecimal data.
• After acquisition, close ROOT by choosing File->Quit in the ROOT window and then stopping DAQ (if in infinite loop) with CTRL-C.
• To perform a fit while acquiring data, add the following arguments: fit 20211103 background.txt backST.txt frontST.txt
  • Ninth argument enables fit option
  • Tenth argument is the folder containing background and shoot-through measurements.
  • Eleventh, twelfth, thirteenth argument are the background, back shoot-throughs and front shoot-throughs respectively.

Experiment Plan

• Background & calibration shoot-throughs (background at all 8 DDC232 full-scale ranges)
• Pencil beams, 70-110 MeV, 5 MeV steps, 2 currents (high/low)
• Live fit demo: pencil beam 95 MeV
• Treatment plan: range steps, 110 MeV-70 MeV, 1 MeV steps, no x-y scanning (demo live fit)
• ±1, 2, 3, 4mm in x-y planes, 95 MeV
• Detector misalignment, ±2°, ±5°, 95 MeV

Experiment Notes

Range calorimeter measurements with Nikon camera + photodiodes.

Images from camera: /unix/pbt/data/uclh/20211102/Nikon

Photodiode hexadecimal data: /unix/pbt/data/uclh/20211102/DDC232

Run number	Full Well Mode	Beam Energy (MeV)	Estimated Range (mm)	Current (nA)	Spot size (mm)	DDC232 FSR (pC)	DDC232 Integration Time (us)	Degrader WET (mm)	Comments	PDL Comparison	CMOS QB Fit	PD QB Fit
0	high	Background	N/A	N/A	N/A	350	170	0	room light on	N/A	N/A	N/A