Privacy and Security Notice
Archived Messages for HALLA_MIN_1997@cebaf.gov: Minutes
Minutes
John LeRose (lerose@CEBAF.GOV)
Thu, 04 Sep 1997 14:10:49 -0400
Minutes of Hall A Group Meeting 2 September 1997
1 General Announcements: (Kees de Jager)
1.1 Meeting tomorrow (3 September) at 1400 to
coordinate activities running in parallel with
Cryotarget commissioning. Anyone with an
activity in mind is invited to attend.
Activities already on the table include:
1.1.1 Parity test measurements
1.1.2 VCS test measurements
1.2 ARC beam energy measurement review was held
last Friday. Arun Saha reports:
1.2.1 Pascal Vernin reviewed the planned method
with emphasis on details of the planned
magnet measurements.
1.2.2 Principal findings/conclusions include:
1.2.2.1 Significant improvement in accuracy
of the energy measurement can be
obtained if the 8 arc dipole are
pulled out and remeasured.
1.2.2.2 Detailed test measurements will be
performed on the “standard” magnet or
some reasonable facsimile in
November.
1.2.2.3 Pending the results of the November
tests the 8 arc magnets will be
pulled out of the tunnel and measured
during the January-February shutdown.
1.2.3 Pascal is preparing a detailed plan for
the test measurements which will be
submitted to the committee for review in 2
weeks. Hope to have the final plan in
place by the beginning of October.
1.3 Notice to all outside users: Any change to any
Hall A instrumentation requires approval of at
least one member of the Hall A staff.
2 Engineering/Installation:
2.1 James Proffitt reports:
2.1.1 Pointing hydraulics are ready to test.
2.1.2 Started work on Dipole interlocks.
2.1.3 Finishing bogey instrumentation.
2.2 Jack Segal reports: Detector stack is out, but
aerogel is not yet removed.
2.3 Paul Brindza reports:
2.3.1 New cable well design on Q2 spool piece
should be done this week.
2.3.2 Design work has been hampered by computer
problems this week.
2.3.3 No news re septum magnet procurement.
2.4 Ed Folts reports:
2.4.1 Continuing with list for downtime.
2.4.2 Trouble shooting Q3
2.4.3 Modifying jib for cryo lines
2.4.4 Assembling turbo valve assembly for cryo
target.
2.4.5 Needs more information re new snout.
2.4.6 Discussing crash bars for doors at top of
truck ramp.
3 Detectors: (Bogdan Wojtsekhowski)
3.1 Have measured flow rate needed to maintain gas
pressure in Aerogels. It is too high. Rate of
bottle changing is unacceptable. Problem seems
to be leaks at PMT’s (not readily accessible to
plug up)
4 Controls: (Javier Gomez)
4.1 Learning new system for fast shutdowns.
4.2 HP has replaced bad console on the HAC
machine
4.3 Working on code for pointing.
4.4 Has discovered that the entrance hole on the
snout is smaller than it should be for the
deuterium experiment.
4.5 Noticed NMR/Hall cable between Q2 and the
Dipole on the electron arm protrudes up into
the drift space more than a comfortable amount.
J. LeRose will check on it.
5 Waterfall target, 16O analysis: (Meihua “Meme”
Liang)
5.1 Working on software change in ESPACE re scaler
readout.
5.2 Survey results had an inconsistency in for the
last measurement on the Electron arm. Problem
was traced to a bad data point.
5.3 Survey group reports that “5 msr” collimator
was off by about 1 mm. Final numbers are not
yet available.
6 Cryotarget: (Jian-Ping Chen)
6.1 Target moved into scattering chamber.
6.2 Survey started last Friday. Should be finished
tomorrow (3 September)
6.3 Installed:
6.3.1 UPS
6.3.2 Lift box
6.3.3 H sensors
6.3.4 Some cabling
6.4 Problem with control box for JT valve found and
repaired.
6.5 All control boxes have been tested
individually. Some minor problems noted and
being worked on.
6.6 “Pretty much on schedule”
7 Michael Kuss reports:
7.1 Working with ESPACE
7.2 Helping Bogdan with Gas Cerenkov PMT’s
8 Discussion: S3 will have to be moved out of the
Hall. Where do we put it? Looking into availability
of space in the high bay area of the EEL.
9 DAQ: (Bob Michaels)
9.1 Working on BPM readout
9.2 Putting a new version of ESPACE. Deadline for
submission of changes is 19 September.
10 Beamline: (Arun Saha)
10.1 Meeting tomorrow (3 September) with RADCON re
locations of ion chambers
10.2 Will need to determine trip points for ion
chambers. Some test time with beam will be
needed.
10.3 Pierre Bertin reports on EP:
10.3.1 All possible mistakes have already been
made.
10.3.2 Working to solve problems. Coda problem
was a combination of cabling and software.
10.3.3 Expect new scintillator to arrive from
Saclay in 2 weeks. Will be placed behind
the Cerenkov.
10.3.4 Making minor adjustments on the target.
10.3.5 Plan to try and take data during
Cryotarget commissioning
10.3.6 Will then need to take more measurements
at NASA.
10.3.7 Ed Folts and Pierre agree after some
discussion that the Beamline will be ready
for vacuum no later than noon on the 26th
of September.
11 Magnet measuring and monitoring/Optics: (John
LeRose)
11.1 Working on document re absolute calibration of
the Hadron arm.
11.2 Have gotten measured quadrupole positions for
the Hadron arm from the survey group. Setup and
run in RAYTRACE using the “Standard Tune”. No
significant changes in matrix elements noticed.
-JJL