• Main INDEX
  • Monthly INDEX
  • PREV
  • NEXT

    User name R. Michaels

    Log entry time 20:38:04 on October29,2007

    Entry number 210516

    keyword=various trigger issues

    1. I fixed the cabling of T1 sent to L-arm. Looks like coax #1 is
    flakey (I avoid it). Also coax #4.

    2. Investigated the L/R asymmetry in trigger rate. It's observed
    even for cosmics. About 9 - 11 Hz on R-arm and 13 - 15 Hz on L-arm.
    (Note, 3.75 Hz of these are EDTM). Noted that with HV off and
    EDTM at few hundred Hz I can see the same rate in both T1,T3.
    Nothing obviously wrong with electronic setup. There is a fair
    amount of after-pulsing on L-arm PMTs, so maybe that's the culprit.

    3. As I said before, a buffered copy of T3 and T4 is sent to R-arm.
    Likewise buffered copies of T1,T2 are sent to L-arm. "Buffered"
    means: trigger goes to fanout#1 which then goes to fanout#2.
    Fanout#1 feeds the scalers and trig. super. and fanout #2 feeds
    the long cable to the other HRS.