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Archived Messages for HALLA_MIN_1996@cebaf.gov: Minutes
Minutes
John LeRose (lerose@CEBAF.GOV)
Fri, 18 Oct 1996 09:21:51 -0400
Minutes of Hall A Group Meeting 15 October 1996
1 Engineering: (Bill Schneider)
1.1 Hadron Dipole:
1.1.1 Is warming up. Expect to get to 300K by the end of the week
and ready to work on by Monday (21 October)
1.1.2 Checked diodes, saw no leakage. Think diodes are OK.
1.2 Waterfall Target:
1.2.1 Waiting for a part. Should be in tomorrow (Wednesday
16 October).
1.2.2 If part doesn’t come in this weekend’s run could be in
jeopardy.
1.3 Spectrometer is set at 16 degrees with 2 cm offset, as last time.
2 Magnet Measuring and Monitoring: (John LeRose)
2.1 Working on calculation of acceptance to post on the www.
2.2 Colloidal suspension measurements on Hadron quadrupoles scheduled
with Jeff Martoff (Temple University) for 5 and 6 November.
3 Beamline: (Arun Saha)
3.1 (e,p) energy measurement:
3.1.1 Local shielding may help with radiation problems . Pierre
Bertin will present a plan next week.
3.1.2 Pierre would like to get e,p working ASAP before interests
wanes in his group.
3.2 ARC energy measurement:
3.2.1 Meeting with Jeff Karn (Accelerator) re arc dipole mapping
3.2.2 Problem when to remove arc dipoles for better field
measurements. Probably to late to try for January ‘97 and need
to verify that equipment can be made to perform adequate
measurements.
3.2.3 9th magnet is in Saclay now. Will arrive at Jefferson Lab in
June ‘97.
3.3 Work is underway in Accelerator Division o develop new beam profile
monitors and 1e-03 current measurement.
4 DAQ: (Bob Michaels)
4.1 Learning how to use mass storage system. Bob will explain it all when
he figures it out himself.
4.2 New Sun Computer is in. Need to setup with fastbus crate etc. Bob
will meet with Jack Segal to arrange space.
5 Trigger Studies:(Meihua Liang)
5.1 Reports that Bill Vulcan has ordered chips to repair V to F Converter
(for beam intensity measurement). Not clear if this will be ready for
next weekend.
5.2 Developing tests to use trigger output combined with intensity
measurements as a luminosity monitor.
6 Controls: (Javier Gomez)
6.1 Working hard at debugging GPIB drivers.
6.2 Q3 current readout upgraded. Can now read current as measured by
the ZFT (Zero Flux Transformer) directly from control screen.
7 Møller Polarimeter: (Sirish Nanda)
7.1 Quadrupoles are here. Chris Curtis is setting up fiducialization.
7.2 Al Guerra is making progress on support structure design.
7.3 Accelerator division giving mixed signals on power supply specs.
Sirish and Larry will discuss off-line.
7.4 DAC for Helmholtz coil is here.
7.5 Re Ops Manual: no update on the good guys/bad guys list.
8 Detectors: (Bogdan Wojtsekhowski)
8.1 Gas Cerenkov:
8.1.1 Adding electronics to generate analog sum of phototubes. Mei
Mei presented schematic.
8.1.2 Hadron arm has high voltage
8.1.3 Replaced pmt on electron arm (had been noisy). Discovered we
have a light leak in the process. Trying to isolate it.
8.2 FPP:
8.2.1 Could use more time on the floor for testing.
8.2.2 Paul Rutt showed results of latest tests. (assorted small
problems: few dead straws, miscabling, low efficiency straws,
etc.)
8.2.3 Chamber 4 could be ready for shipping from Rutgers this
weekend. Only question is where to put it when it gets here.
8.3 Bogdan requests that J. LeRose calculate field settings for a
deliberately mistuned spectrometer such that the beam envelope totally
fill the shower counters.
8.4 Information from our poster displayed at the DNP meeting will be
posted on the www.
9 There will be a top level review of TJNAF on 28 October. Bill Schneider is
advised to prepare the Hall for visitors.
10 Electronics: (Jack Segal)
10.1 Working on cabling in the shielding hut. Biggest problem is getting
connectors.
10.2 Could use assistance from about 4 people tomorrow (Wednesday
16 October). Interested volunteers should see Jack in the Hall
tomorrow.
11 Cryotarget: (Jian-Ping Chen)
11.1 Gas panel preliminary drawings done.
11.2 Tech’s assembling motors.
11.3 Lars Ewell preparing for chemical etching and coating. Expecting visit
from expert at U.Md. next Monday (21 October)
11.4 Frequency controller: designing and putting together a different type
for comparison
11.5 Students working on:
11.5.1 Instrumentation wiring
11.5.2 Software
11.5.3 High power heaters
11.5.4 Breakout box
11.6 Cal State LA brought He cell last week for machining here. Work
completed on Saturday.
11.7 Bill Schneider comments that after reviewing drawings re interface
with the spectrometer he recommends using a rollaway rather than
permanent stairs.
12 Pascal Vernin asks about status of power supply for Compton Polarimeter.
Sirish answers that it has been ordered. Pascal reminds us that it should be
delivered to Saclay.
-JJL