PREX/CREX Oct 9, 2018 10:00am

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  1. Update on Hall A BPM issues: Cameron HAlog3604073, HAlog3604212
    • CC: the problem has been fixed in the injector before we were able to diagnose it with our DAQ
    • KP: we should look at the BCM and run our DAQ. CC: I took data several times and we should be ready if problem comes back
    • CG: Musson told us that the cavity BPMs are ok now. YT: tried to run the DAQ, but I need to figure out what channels are the cavity BPMs.
    • CC: some of the VQWK channels are bad. KP: we should document this in the haplog on top of the wiki
    • CC: Joe Grames will keep an eye out to see if he can figure out what might be the culprit for the noise from the injector.
    • CC: have some references from Tom Powers (the designer for the stripline electronics) and he thinks this is not abnormal. KP: you should put these in the docDB
  2. Update on collimator shielding dose/heating: Adam & Victoria haplog3547 haplog3548
    • AZ: updated the geometry upstream and around the collimator: added gate valve, changed the material to stainless steel, added conical tube between the collimator box and septum, extra 6 in of plastic that existed in the CAD but not in our sim
    • AZ: the main plastic block sees a drop in dose by half. I credit this to the gate valve shielding the US and the new plastic shielding block in front of it.
    • KP: the heating seems to be an issue, so need to figure out some cooling but otherwise i don’t see any major issue in terms of radiation.
    • VO: I did a similar study in FLUKA but with a slightly simpler geometry, but that captures the major features. The results are similar to what Adam got. My HDPE is flush on the stainless steel. Within 1 cm radially out the HDPE has about 1e5 dose.
    • VO: when i had a thicker (8mm vs 1.5mm) “pipe” for the bellows the dose on the HDPE was smaller by one order of magnitude. CG: we should make sure we have the correct thickness of the bellows looking at “effective thickness”
    • SR: we should do a back of the envelope calculation of the heat transfer for that thickness of steel. KP: we'll look into it.


Victoria O, Sanghwa P, Amali P, Kent P, Ciprian G, Cameron C, Adam Z, Caryn P, Chandon G, David A, Devi A, Dustin M, Jinlong Z, Paul K, Rich H, Ryan R, Seamus R, Tao Y, Ye Tian, Eric K,


KK, Dave G,