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Archived Messages for HALLA_MIN_1996@cebaf.gov: Minutes
Minutes
John LeRose (lerose@CEBAF.GOV)
Fri, 14 Jun 1996 09:19:44 -0400
Minutes of Hall A Group Meeting 11 June 1996
I. Budget: We will get the money we asked for to complete Hall A this year.
Things are still very tight and we can only make absolutely necessary purchases.
II. Complaint: People are becoming lax re the safety dress code in the Hall (hard
hats, long pants, eye protection, steel toed shoes, etc.). The Hall is still officially
a construction site. In the future violators will not be permitted to remain in the
Hall.
III. Meeting: Larry wants to meet with all Hall A graduate students and post-docs
on Friday at 13:00. Room to be arranged.
IV. Engineering: (Bill Schneider)
A. Installing half inch plate on beam side of shielding huts.
B. Pouring concrete all day tomorrow (12 June)
C. Sprinkler system being installed on Hadron Arm. Electron arm next
week.
D. Set tentative date of 30 June for colloidal suspension measurements on
Q3 and Q1.
E. Q1:
1. Changing a card seems to have fixed the cryo-valve problem.
Further testing underway.
2. Following the visit of Claude Lemond we have come to an
equitable agreement with Saclay re the modifications necessary
to adapt Q1 for use with our control systems.
F. Hope to complete cryogenics installation by the end of June.
G. Need drawings from Rutgers to fix sieve slit.
V. Beamline: (Arun Saha)
A. ARC:
1. Optics pipe suspended from the ceiling
2. Shield wall is installed up to the optics pipe. Should be finished
by the end of the week.
3. Super harp ready for installation in Hall C for testing
B. e,e’p energy measurement: Large parts have come in. Installation details
to be worked out.
C. Target Chamber: Dick Lindgren looking into the possibility of making
the 2 large windows at U.Va.
D. Current loop problem with arc dipoles mentioned by Larry Cardman.
Pascal Vernin will look into it.
VI. Magnet Measuring and Monitoring: (John LeRose)
A. Q3 measurements underway
1. Preliminary results shown by Gilles Quemener
2. Problem of power supply not regulating well at large negative
currents discussed. Quick solution for present purposes is don’t
map at large negative currents.
VII. DAQ: (Bob Michaels) Put spare system disk in today (adaq1/2)
VIII. Commissioning: (Eddy Offermann)
A. FAX from Rutgers due today re collimator box modifications.
B. Expect delivery of the Hadron Arm collimator box 20 June.
C. Usefulness of toggle valve discussed
D. Data analysis meeting Wednesday (12 June) 10-12 L207
IX. Detectors: (Bogdan Wojtsekhowski)
A. VDC’s:
1. Wish list is coming true.
2. Data analysis ongoing; cutting off the tail on the drift time
spectra increases efficiency.
B. Scintillators: observed puzzling variation of amplitude of signal from
one paddle.
C. Preshower Counters: started modification of support structure.
D. Shower Counters: signed off on contract for amplifiers.
E. Gas Cerenkov: Discussed viability of keeping CO2 bottles outside in the
gas shed. Looks OK.
X. Controls: (Javier Gomez)
A. Testing Danphysik Power Supply (Q1) sometime this week. Recent fix
in Hall C Danphysik power supply mentioned. Javier will talk to Bill
Vulcan.
B. Creating 2nd subnet for Power Supply controls protection.
C. Discussion of assorted computer problems for slow controls.
D. Discussion of future setup (ATM etc.)
XI. Polarimeters and cryotargets: (Jian-Ping Chen)
A. Møller:
1. Dipole and Quads are in Lexington Ky. !!!!!!
2. Have revisited optics. Everything seems OK. Preparing written
document.
B. Compton: Have had lengthy discussions with V. Lebedev re his new
scheme. There are advantages and disadvantages. Will be discussed
further. At present the consensus seems to be to not change plans.
C. Cryotarget:
1. Gas flow scematic drawing is being finalized. Now available for
anyone who wants to have input to the design
2. Will show floor plan next week for one gas panel and tanks
3. Finished 1st set of Temperature Sensor calibrations.
4. Task list for Hall A Cryotarget project shown and discussed.
a) L. Weinstein (ODU) has agreed to work on the lifting
mechanism for 1 month over the summer.
b) W. Boeglin (FIU) will come to TJNAF for one month in
July to work on cryotarget
c) F. Duncan has agreed to make the Hall A Cryotarget
control his top priority for the next several months.
d) Student/Post-doc help is still urgently needed.
5. Hall C Cryotarget:
a) Preliminary results of tests of cooling power presented
and discussed.
b) Leaks have been found.
XII. User Report: Riat Suliman (Kent State) has been at TJNAF for 80 days
working on:
A. Debugging DAQ
B. Software improvements
C. Commissioning data analysis
XIII. Mike Finn expresses thanks for courtesy and cooperation extended to him
during his sabbatical stay at TJNAF and introduces new graduate student,
Krishni??, working on FPP.
XIV. Party in celebration of recent progress in Hall A will be held this Friday
(14 June) in the residence facility 14:00-16:00
-JJL