Wednesday, February 19, 2020, 2:00 pm EST

Back to Main Compton Page >> Compton Meetings

*********BLUEJEANS CALL-IN INSTRUCTIONS*********
----------------------------------------------------
1. Dial Toll-Free Number: 1-888-240-2560 (U.S. & Canada)
2. International participants dial:
Toll Number: 1-408-740-7256
3. Enter meeting ID:140287970

Desktop sharing:
https://bluejeans.com/140287970 

Agenda

Meeting room = Counting House Meeting Room

General

• Compton position lock, orbit
• Backgrounds

Electron detector

• Recent tests
• QWAD installation?

Laser

• Cavity/laser status

Photon Detector

• Spectrum fitting for collimator offset (low threshold, high threshold)

Analysis

• Online analysis results

Minutes

1. Photon Detector
   1. Back on the high threshold after the low threshold test.
   2. Progress in doing rate normalization of background. (JC)
   3. 500 ns Gate prevents triggering on tails of pulses. Is it long enough?
   4. Possibility of using the jaws to check centering on the collimator?
   5. Adam implemented a new cycle selector which recovers a lot of data.
   6. Do the backgrounds have an asymmetry.
2. Electron Detector
   1. Ready to for high rate. Waiting for access to install QWADs (1 hours to change it plus time to make sure it works.)
   2. Will run with current electronic with both blocked and unblocked mode.
      1. Brian Moffat working on decoding the blocked mode.
      2. Hanjie and Iris working on the analysis.
3. Laser
   1. Had a problem with coupling between fast and slow legs leading to a slow runaway correction which limited locking time. This was fixed by removing the slow signal from the the box that amplifies the fast signal and acted as a feedthrough fro the slow signal.
   2. There is a thermal effect on the locking after the cavity hasn't locked for a while. Are the mirrors deteriorating?
   3. We have 2.2 kW in the cavity.