FROM: B. Mecking
TO: CLAS Collaborators
SUBJECT: Requests for Beam Time
DATE: 11-March-1998
In a recent (02/19/1998) memo, the Nuclear Physics Experiment Scheduling
Committee asked the spokespersons of approved Jefferson Lab experiments to
submit their requests for beam time for the first half of calendar year 1999
by Tuesday, March 17, 1998.
Since the CLAS Collaboration has determined the sequence of runs, there is no
need for the spokespersons of CLAS experiments to submit these requests
individually.
Just as a reminder the CLAS Collaboration (at the collaboration meeting on
September 5, 1997) has agreed on the following sequence of runs:
Run PAC PAC Calendar Year
Group days rating days
-----------------------------------------------------------
e1 19 A- 38 1997/8
g1 22 A- 44 1998
g6 10 A- 20 1998
eg1 52 A 104 1998
e2 15 B+ 30 1999, 1. half
e1 25 A- 50 1999, 1. half
g2 10 B+ 20 1999, 1. half
g6 10 A- 20
g1 16 A- 33
e5 20 B+ 33
e1 15 A- 30
g7 12 B+ 20
g8 11 B+ 18
g3 30 B 50
eg1 52 A 87
e2 25 B+ 42
e6 16 B+ 27
g1 21 A- 35
g2 18 B+ 30
g8 9 B+ 15
e1 47 A- 78
In CY1998, we scheduled a total of 223 days for Hall B running (21 days for
commissioning, and 202 days for production running). Based on this model we
will be able to schedule a total of about 100 days in the first half of 1999.
This will allow to run e2 (1. period), e1 (2. period), and g2 (1. period).
This plan will be submitted to the NPES. The plan is obviously contingent on
the timely availability of the Hall B polarized target which is proceeding on
an extremely tight schedule. At the last CLAS Collaboration meeting, this
problem was discussed, and the following fall-back position was agreed upon:
If there is a major delay in the availability of the polarized
target, we will change to the standard electron configuration and
run the polarized part of e1 till the polarized target is ready.
I propose to make this position more precise by adding the following
statements:
1. If there is less than a four week delay in the availability of the
polarized target, we will go into a maintenance/repair period.
2. If we start e1, we will run it for at least four weeks even if the
polarized target becomes available earlier. Beam energies will be the same
as the ones required for eg1.
3. If the polarized target is not ready to be installed by October 1, the eg1
run in 1998 will be canceled.
Unless I hear any violent objections this plan will be submitted to the NPES.