Proton Calorimetry/Experimental Runs/2022/MayLED

Optical isolation tests using LED fibre in D27.

Aim: Investigate optimal material to use to optically isolate unpainted sheets and whether single layers of material provide sufficient isolation.

Notes

• DDC232 settings: 170us integration time and measured 10000 samples per run.
• Signal Generator settings: 0 ps delay, 500 kHz, 300 ns width, 5 ns leading edge and trailing edge, 6V high, 0V low.
• Fibres used: 25 and 29 (25 used for single injection tests).
• Sheets used: 84, 82, 81, 80, 79, 78, 77, 76, 75
• Materials tested: none, white paper (0.01 mm thick), black card (0.02 mm thick), mylar foil (0.006 mm thick). Materials cut into 10 cm x 10 cm layers and placed in-between sheets.

Run	Description	Graph
1	No material dark noise test, 12.5pC
2	No material cross-talk test, 12.5pC
3	No material light level test sheet 1, 350pC
4	D27, CMOS off, 12.5pC
5	D109, CMOS on, 350pC
6	D109, CMOS on, 12.5pC
7	D109, CMOS off, 350pC
8	D109, CMOS off, 12.5pC
9	D109, CMOS on, 12.5pC. Detector housing grounded using ground pin of FPGA. Grounded using optical breadboard inside detector.
10	D109, CMOS on, 12.5pC. Previous grounding seemed ineffective. Now grounded by attaching clip to metal on outside face of detector enclosure.
11	D109, CMOS off, 12.5pC, grounded.
12	D27, CMOS off, 12.5pC, grounded.
13	D27, CMOS off, 12.5pC
14	D27, CMOS off, 12.5pC, grounded, LED. LED pulse of 1MHz, 6V height and 500ns width. Injected into single scintillator sheet coupled to photodiode 16.