PREX/CREX Nov 27, 2018 10:00am
From PREX Wiki
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- Cavity monitors: Ye/Bob docDB280
- YT: low current test happened this past Sunday ( a total of 50 min, without moving the beam around ).
- YT: from top to bottom: x: stripline E, stripline A, B, C, D. Then y (same order). Last for: charge info from B, C, D. last one is hallA average BCM
- BM: the rate is from scalers looking at a solid multi foil target.
- BM: cosmic rate is 5 Hz. it would be better to have a thicker target.
- KP: how did they use to set nA current? BM: they use a Faraday cup.
- CG: why does E read at 100nA but not A? YT: not sure
- YT: we did a rough calibration of the cavity intensity.
- KK: how about pedestal, non linearities and gain calibration? YT: this is just a rough test, more data is needed to get a proper calibration. BM: we will use the starting rate from the target and we plan to analyze it.
- KK: we should not assume that the Pcup reading is correct. KP: it principle it should work fine but there is a lot that can happen in the machine.
- KK: what beam energy is this? CG: i think it was 2 pass, 4.4 GeV.
- KP: do know if the position is the same for different currents? YT: since we haven’t calibrated it, it’s not clear that the strip traces are a good indicator. BM: we will follow up with a study where we wiggle the beam.
- Stripline BPMs: Caryn haplog3547
- CP: it seems that the BPMs have large RMSs from jumping between 3 different levels.
- CP: the y- wire channel seems to be the one with the problem
- CP: there was a odd behavior for BPMa while E was seeing the issue.
- KP: APEX will want these working and we should try to pursue fixing these
- PK: are the BPM parameters archived? YT: will try to retrieve this information.
- PK: for the ramping signal: the signal on the ADC should just hit the wall and stay there. I think this is due to the voltage into the ADC. CC: this was probably my fault since I was doing testing. Cameron has made a page for keeping track of testing and commissioning runs leading up to Prex/Crex - DAQ_Testing/Run_List
- CP: also analyzed 4642. and it shows similar issues. KP: it does look like the change in width is due to the auto-gain function
- CG: will talk to Doug and we’ll get the BPMs working before APEX
- Schedule for PQB time (Mar8-11th): Ciprian slides
- KP: does APEX require cooldown (radiation)? Should we limit our beam current? CG: will investigate
- DG: for Moller you can use the BCMs if they work well at 0.5 uA.
- Schedule for next week: Ciprian Weekly Meeting Discussion Topics
- Kent: Outstanding design elements
- Caryn: Injector setup and feedback (push back by one week)
- Victoria/Ye: Beam modulation
- Dustin: GEMs (in Ca for beam test, but will try to make it)
Amali P, Ye T, Dave G, Sanghwa P, Ciprian G, Cameron C, Chandan G, Devi A, Eric K, Guido U, Jinlong Z, Kent P, KK, Paul S, Bob M, Tou Y, Victoria O, Rich H, Ryan R, Silviu D, Caryn P,