TO: CLAS Collaboration
FROM: B. Mecking
SUBJECT: Hall B Schedule Change
DATE: 22-April-1998
A review of the experimental readiness of the eg1 run was held on April 9,
1998 at JLab. The review committee, chaired by John Domingo, was very
concerned about the tight schedule and the potential impact of the eg1 effort
on the readiness of the Gen experiment in Hall C. The committee made a strong
recommendation to delay the installation of the Hall B polarized target by one
month, mainly to reduce the work load on the few critical polarized target
experts.
The CLAS Collaboration Scheduling Committee has discussed the necessary
schedule change during a conference call on April 20, and has come up with the
following recommendation:
Time Activity Comment
04/23 - 04/30 continue tagger, Moller, and CLAS commissioning
05/01 - 06/01 run g1 (Miskimen, 2.48 GeV)
06/02 - 06/08 maintenance and facility development
06/09 - 07/02 run g6 (Marchand, 4.23 GeV)
07/03 - 07/12 He processing of accelerator cavities
re-install Cerenkov counters (if ready)
07/13 - 07/26 continue to run g1 at 1.83 GeV 1)
07/27 start removing standard cryo-target and beam line
start drift chamber repair (top 2 Region III)
if polarized target installation is delayed
beyond 08/03/98.
if the polarized target is on schedule for
installation on 08/03/98, drift chamber repair
will be delayed till January 1999
08/03 - 08/18 polarized target installation
re-install remaining Cerenkov counters
08/19 - 08/20 eg1 commissioning
08/21 - 12/24 run eg1 (for 91 days)
Comments
1) The g1 run extension will restore most of the time lost at the beginning of
the g1 run (g1 was supposed to start 04/13/98). Three-pass beam will not be
available, since it is occupied by Gen in Hall C. The 1.83 GeV (2-pass)
beam energy had originally been arranged for eg1. At 1.83 GeV, one will get
perfect longitudinal polarization (at the 75% level). While this energy is
too low for some of the g1 experiments, it will represent a unique
opportunity to get circularly polarized photons with high polarization,
e.g. for measuring the polarization transfer from circularly polarized
photons to photo-produced Lambda's.