• Main INDEX
  • Monthly INDEX
  • PREV
  • NEXT

    User name Templon

    Log entry time 07:56:20 on June 1,2000

    Entry number 42709

    keyword=running shift summary

    production runs theta=135, phi=0. beam current about 50 uA.

    polarization about 73 percent.

    run 1589 - 1.25 M events
    run 1590 - 1.25 M
    run 1591 - deadtime soars to 80 percent. end of run failed first time too,
    ..... second attempt to end run works.
    run 1592 - deadtime back to "normal" (29 percent!!); oops, no...
    ..... deadtime climbs near end of run. 89,000 events only.

    perhaps rate is too high; try changing prescale factors noone on shift is sure
    what ps2 and ps4 are.

    attempt change: ps2 500->600
    ...........................ps4 450->500

    run 1593 - again stopped due to high dead time!
    run 1594 - 1.25 M

    called M. Jones about deadtime problem. possible reason: replaying same run
    .... as was being acquired; for some runs we were doing this. this is bad at
    .... high rates. another possible reason is file copying; will look for this if it
    .... happens again. i hope staying away from replaying a still-open file will
    .... solve the problem.

    run 1595 - 1.25 M
    run 1596 - 1.25 M
    run 1597 - 1.25 M
    run 1598 - 1.25 M
    run 1599 - 1.25 M
    run 1600 - 1.25 M
    run 1601 - 1.25 M
    run 1602 - 70k events, high deadtime, run killed. first end run failed, second
    ...................attempt failed as well although events stop coming in. third
    ...................attempt also reports end of run failed. kill coda and restart

    run 1603 - no events coming in. stopped run, did "reset" from CODA menu,
    ...................then stuff started to work again.

    run 1604 - 1.25 M
    run 1605 - 1.25 M
    run 1606 - 1.25 M
    run 1607 - 1.25 M
    run 1608 - 1.25 M
    run 1609 - 1.25 M
    run 1610 - 1.25 M
    run 1611 - 1.25 M
    run 1612 - 1.25 M
    run 1613 - 1.25 M
    run 1614 - 1.25 M
    run 1615 - 1.25 M
    run 1616 - 1.25 M
    run 1617 - high deadtime and problems ending run. reset CODA from runcontrol
    ...................GUI to "force" run end.
    run 1618 - 470k - stop to check FPP HV (hole in spectra)
    at same time, MCC asks for beam for 5 minutes for injector check.
    at same time, ramping down relevant FPP HV (master 8.0.0). HV console
    indicated that voltage was fine, but hole looked more convincing. new evidence
    (see HALOG 42682 and followups) is that problem with FPP only exists
    for one run.

    run 1619 - junk run, still changing HVs on FPP
    run 1620 - junk, coda crash
    run 1621 - 1.25 M
    run 1622 - 1.25 M
    run 1623 - 1.0 M - stopped due to cavity problem with accelerator.
    .......................MCC says the cavity must be bypassed, will take ten or so minutes
    .
    run 1624 - 1.25 M
    run 1625 - 1.25 M
    run 1626 - 1.25 M
    run 1627 - 1.25 M
    run 1628 ... in progress at shift end