Day Shift, Sunday, August 25, 2002

Carlos,Eric

8:00AM RF problems, no beam for at least one hour (MCC said).

9:20AM RF problems, no beam for at least one hour (MCC said).

10:00AM Eugene calls about E-couters. first 64 E-counters scalers are
down.  (known from before). They were all of them at 1850V. Eugene
wants to restore previous values.

10:45AM Eugene tune thresholds of E-counters around 90 (that were
hot). Now everything seems OK (as by no-beam MOR counts). Couter 166
is perhaps still no OK (need to be looked at later).

11:00 Mark and Ashot attend meeting at MCC with PD. Mark Pitt and Jay
Benesch were also there.

  o RF separator problem is being worked on. There is a bad power
    supply for one of the cavities. Right now there is a magnet
    providing the kick for directing the beam to Hall C, but this
    configuration prevents sending the beam to us as well. Woody is
    allegedly working on it.

  o When the RF separation hardware has been fixed, Jay will take the
    machine (Hall C goes down). He has one hour time limit to

    a) Re-establish RF separation.

    b) Address a dispersion problem in the machine (i. e., remove
       energy-position correlations in the beam).

    c) Work on a mismatch of quad magnets with the betatron profile of
       the machine if there is time.

    At the end of this it is hoped that we have two-hall operation and
    that our aspect ratio is better. Note that (b) and (c) should help
    Hall C as well.

  o When this tuning is done there may be additional tuning to do in
    our beamline to establish a better photon beam aspect ratio. This
    can be done without affecting Hall C.

  o The machine is scheduled to go down tomorrow morning at 9:00 am
    for a variety of fixes; among them re-establishing orbit locks (we
    have been running without them) and attempting to increase the
    beam current to Hall C. We might be down until the end of the day
    shift depending on how things go.

11:30AM Eugene and Valery in Hall Contrlled Access
Look for E-counter previous HV values in tagger logbook and powercycle ADML

12:00 Cycled power on ADML crate 3. Now we see all E-counters on scalers, 
except the first 64 which do not have scalers.
Lookup for the E-counter HV setting eneded up with the last printed out 
voltages from g8a, in average they are all around 1900V.

2:00PM Bad Beam back. Worse than last night. MCC sees good beam in 21 and bad in 23 . suspect scrapping in between (Gniometer and Moller)? They will check optics.

3:15 Still sterring beam. Still streched in y between 21 and 23.