Proton Calorimetry/Experimental Runs/2021/Apr22

Noise tests of UCLH beam test setup in D109/D27.

Aim: Investigate source of external electronic noise observed at UCLH by measuring dark noise in lab/office with CMOS sensor turned off/on.

Notes

• D27 is an electronically noisy lab whereas D109 is a quieter office (though still not a perfectly shielded environment).
• Test 2 DDC232 boards coupled to scintillator stack.
• CMOS sensor coupled to scintillator stack on perpendicular face.
• Both CMOS sensor daughter board and DDC232 Nexys Video board in detector enclosure.
• In all runs, an integration time of 170us is used.
• Video steps through individual consecutive acquisitions at frame rate shown. Each frame represents 170us in time.
• Histogram of one photodiode also provided. Expect to see clean gaussian shape if no external noise is being picked up.
  • Signal photodiode shown for Run 14.
• Note the absolute value of the y-scale, which differs in some clips.

Videos and thumbnails saved in /unix/www/html/pbt/wikiData/movies/DDC232/210422

Run	Description	Histogram	Video
1	D27, CMOS on, 350pC
2	D27, CMOS on, 12.5pC
3	D27, CMOS off, 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.