Compton Doc Portal

The following is intended as a DAQ, and detector guide for Compton experts. Shifters and other non-experts should only use this page for reference. Contact a Compton expert if making changes are necessary.

Compton Electron Detector

How to check the electron detector's position status

Compton HV GUI Guide

Finger PMT Controls

The HV GUI only controls the finger PMTs for the PREX run period. The following is a list of instructions in order to turn on or off their voltage.

1. First log into adaqsc with user aslow.
2. Navigate to directory ~/slowc/ and run ./hvs BEAMLINE
3. Once the GUI is open navigate to S.6 and scroll down to channels 10, and 11.
4. To enable finger PMTs make sure channels are set to the appropriate voltage and that HV is turned on.

The correct voltages for the finger PMTs are as follows:

	Slot	Channel	HV
Side (V) Finger	SL-6	CH-10	-950 V
Top (H) Finger	SL-6	CH-11	-1000 V
GSO (PhDet - Full Gain)	SL-12	CH-11	-1612 V
GSO (PhDet - 90% Gain)	SL-12	CH-11	-1607 V
GSO (PhDet - 70% Gain)	SL-12	CH-11	-1592 V
GSO (PhDetector - 50% Gain)	SL-12	Ch-11	-1569 V

Table Scintillators

1. In the same GUI above navigate to S.9.
2. Ensure that channels 0, 1, 2, and 3 are set +1800 V.

The table scintillators are classified as follows:

	Slot	Channel	HV
DS Top	SL-9	CH-0	+1800 V
DS Bottom	SL-9	CH-1	+1800 V
US BR	SL-9	CH-2	+1800 V
US BL	SL-9	CH-3	+1800 V

Photon Detector Table

Normal Operation

1. From the slow controls in JMenu, open up EDM Hall A and JTabs Hall A.
2. Navigate Hall A->Compton->Controls. Look for the calorimeter on the design, click the button select table.
3. Adjust the table to the desired x and y position.

Troubleshooting

If the table gets stuck or unresponsive and errors won't disappear, follow these instructions to reset the table manually:

1. Take the double suction cup pump next to the compton terminal.
2. Use the pump to lift the tile adjacent to the wall in front of the compton terminal. If you are standing in front of the terminal, the correct tile should be the one beneath your left foot.
   1. Be cautious not to injure your hand when lifting the tile! The tile is very heavy and can cause serious injury if mishandled!
3. Once the tile is removed from underneath pull out the brown box with switches on it.
   1. NOTE: There is another box under there labeled "kill switch." Do not touch this box unless absolutely necessary!
4. Once you have the brown box, flip the switch labeled "On/Off." If the red LED does not light, don't worry, that LED is dying.
5. Flick the switch labeled "up" to begin moving the table manually. After just a second the table should be moved enough to be responsive, so flick the switch back.
6. Once the table controls are responsive again, flick the switch to "Off," put back the box, and replace the tile, being careful not to pinch your fingers.

Taking Special Runs

LED Pulser Run

This instruction guide assumes you know how to use CODA to start and stop runs.

1. Before running CODA run command ComptonConfig from the compton machine.
2. From the options available select "Pulser On, Pulser Trigger." Click "Apply" and then "Done."
   1. If possible use comptcam1 to verify that the pulser box is turned on. If you can't see the pulser box LED from the camera angle then skip this step.
   2. You should also look at the parameters set in ~/crl/PulserOn_TrigPulser.flags If the pulser flags look good then you can proceed. If not, edit the flags file to your liking.
3. Starting the next run on CODA will start the pulser run.
4. Start a run in CODA the pulser will be
5. Start a run. The pulser will be on.

IP Scaler Channels

Channel #	Descr
0	-Not Connected-
1	40 MHz Clock
2	BPM2A Y-
3	BPM2A Y+
4	BPM2A X-
5	BPM2A X+
6	BPM2B Y-
7	BPM2B Y+
8	BPM2B X-
9	BPM2B X+
10	HFinger (Top)
11	VFinger (Side)
12	CavPower
13	Trig (Low Thresh)
14	BCM
15	-Not Connected-

Run Scaler Channels

Channel #	Descr
0	ComptonDSbg1
1	ComptonDSbg2
2	40 MHz Clock
3	40 MHz Clock
4	ComptonUSbg1
5	MPS Scaler
6	ComptonCentralRateHigh
7	ComptonCentralRate
8	-Not Connected-
9	-Not Connected-
10	HFinger (Top)
11	VFinger (Side)
12	PMT Trigger Rate
13	ComptonUSbg2
14	PMT mid thresh rate
15	-Not Connected-

Expert Links and Controls

• HACOMPTON
• Compton Log
• Laser Table Camera (ComptCam1)
• Jaws Position Camera (ComptCam2)
• Compton Jaws Control

Default Settings and Positions

In addition to the HV's listed above, we also have a visual center on the photon detector

Date	X (mm)	Y (mm)	Centering Method
2019-06-17	70	33.5	Visual
2019-11-20	70	32.5	Visual
2020-01-16	72.75	30.7	Fingers

The jaws have their own positions as well:

Aperture (mm)	y center (mm)	Comment
1.50	-46.00	HOME position