Difference between revisions of "PITA scan HOWTO"

Revision as of 16:27, 3 August 2019

Turn Parity feedback off by doing ctrl-c (or ctrl-\) in the terminal running feedback. If feedback is stopped, runbird will show that Vpita has stopped changing every 10sec.
one Parity feedback is stopped, call MCC and request the Rotating Half Wave Plate be set to 500. The parity alarm will go off. This is ok.
Start a new run and label it "Parity Scan" and in the comments say "PITA scan, RHWP=500"
Do the following to run the auto-mated PITA scan (PITA scan)
- ssh apar@adaq1
- cd ~/yufan/scan
- /scan.py pita
The auto-scan should take a just few minutes (so long as the beam is >67uA) and the PITA scan will set Vpita +-1000counts or so. You'll be able to see Vpita change in the terminal, in runbird, or in the Parity RTP Screen.
When the script ends, the terminal will stop outputting text and Vpita should have returned to its orginal value.
Call MCC and request the Rotating Half Wave Plate be set back to 1.
Go to the Parity alarm handler and make sure all the alarms have been turned back on and are reading green.
Restart Parity feedback in the terminal by typing ./feedback_ana (see https://prex.jlab.org/wiki/index.php/Parity_feedback_and_Analysis_Minder for help)

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 *one Parity feedback is stopped, call MCC and request the Rotating Half Wave Plate be set to 500. The parity alarm will go off. This is ok.
 *Start a new run and label it "Parity Scan" and in the comments say "PITA scan, RHWP=500"
-*Do the following to run the auto-mated PITA scan  (For further details on the PITA scan script see [[PITA scan]])
+*Do the following to run the auto-mated PITA scan  ([[PITA scan]])
 **ssh apar@adaq1
 **cd ~/yufan/scan