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Archived Messages for HALLA_MIN_1996@cebaf.gov: Minutes
Minutes
John LeRose (lerose@CEBAF.GOV)
Tue, 08 Oct 1996 15:12:21 -0400
Minutes of Hall A Group Meeting 1 October 1996
1 Born: Jennifer Judith Markowitz, 7 lb. 7oz., 19 September 1996.
Congratulations to Pete and Judy.
2 Larry Cardman reviews the Hall A Beam Schedule:
2.1 What we will actually do will be sequential. Dates on the schedule are
optimistic guesses as to when things could happen. The sequence is
more important than the dates.
2.2 Hall A run schedule requirements document will be posted on the www
(http://www.cebaf.gov/halla/minutes/halla_97.html)
2.3 Caveat re 16O experiments. If either experiment has technical problems
one won’t hold the other back.
2.4 Question re status of the fast raster. Bob Michaels is taking care of it.
All hardware except the power supply has been purchased. Installation
details need to be worked out.
3 Engineering: (Bill Schneider)
3.1 Dynapower rep is here helping to checkout the Hadron-arm dipole
power supply. Also helping with some small problems with Electron
arm dipole power supply.
3.2 Electron arm back at 16 degrees.
3.3 All contracts except delay line installation are finished.
3.4 7 mil kapton on order for large window on scattering chamber. When it
comes in we will be able to go to any angle (between 12.5 and 160)
3.5 Alignment problems with Hadron arm. Exit flange on dipole appears to
be off by about 1”.
3.6 Planning colloidal suspension measurements for final alignment of
quadrupole 3rd or 4th week of October.
4 Commissioning: (Eddy Offermann)
4.1 Reviewed results of last weeks run.
4.2 Plan for next weekend. Go back to 16 degrees and deliberately mispoint
spectrometer about 3 cm. Will to y0 studies with the sieve.
5 Magnet Measuring and monitoring: (John LeRose)
5.1 Meeting next Thursday (3 October) for technical review of plans for
Septum magnets.
5.2 Making progress on dipole maps. Hopefully more to report next week.
5.3 Plea made for more detailed and careful logging of magnet settings
during commissioning runs.
6 Beamline: (Arun Saha)
6.1 Obstruction in Beamline positively identified as BPM antenna.
6.2 Following up on injector slit A implementation. (Will allow us to run at
higher currents)
6.3 Report on Current monitoring and measuring. (Branco Vlahovic)
6.3.1 Showed mechanical layout and electronics schematic.
6.3.2 Shower results of recent measurements
6.3.3 Questions re long term stability
6.3.4 Why isn’t current information in the data stream? Nobody is
working on it.
6.4 C. Geraud reviewed:
6.4.1 Calibration procedure to cross calibrate Unser and Cavities.
6.4.2 Beam Current Monitor operations. Reboot the computer with
on/off switch in the back. If that doesn’t work call in the experts
(Branco or Geraud)
7 DAQ: (Bob Michaels)
7.1 Reviewed trigger tests last weekend. MeiMei is analyzing.
7.2 Bob is investigating problem of configuration string not getting into the
data string.
7.3 Bob will communicate to the electronics group our need for a
supervisor module for the fast raster.
8 Cryotarget: (Jian-Ping Chen)
8.1 Meeting last Friday (27 September) re installation schedule. Minutes
available from Jian-Ping and on www.
8.2 Design work in progress on:
8.2.1 service window on Cryo can
8.2.2 gas flow schematics
8.2.3 cryo gasline layout
8.2.4 cable trays
8.2.5 Stand alone High power heater system
8.3 Techs working on heat exchangers and motor housing.
8.4 Students working on:
8.4.1 Temperature sensor readout breakout box (completed)
8.4.2 Code for frequency control
8.5 JT valve control electronics parts are here.
8.6 Frequency controller for motor tested in LN2
9 Controls: (Javier Gomez)
9.1 Working on EPICS drivers for Industry Pack
9.2 Working on Vertical Positioning System.
10 Data Analysis: (Meihua Liang)
10.1 Reports that runsheet on-line information is not exact.
10.1.1 Bob explains setup procedure.
10.1.2 This is an identified known problem.
10.1.3 Run sheet is not complete
10.1.4 Bob will work on a quick fix.
10.2 Discussion of whether we want “standard trigger” or something else.
10.3 Problem noted with shower detector #64
11 Møller Polarimeter and Ops manual : ( Sirish Nanda)
11.1 Møller:
11.1.1 Meeting last Monday (30 September)
11.1.2 Installation Plan:
11.1.2.1 Phase I: Q1 and Q2 (serve as Beamline quads as well)
installed by Christmas.
11.1.2.2 Phase II: Dipole and detector box. April-May
11.1.2.3 Phase III: Targets, electronics, etc. January
11.2 Ops manual: still a lot of contributions outstanding. Larry encourages us
all to get to work on this.
12 Chamber Gas System: (Howard Fenker)
12.1 All interlocks to Electron-arm tested and ready.
12.2 Exhaust line from shielding hut to pivot the last thing to do.
12.3 Discussion of gas supply adequacy and procedures for shutoff to
conserve gas.. Suggested that if you turn the gas off you inform
everyone on the TOSP and make a note in the logbook.
13 Detectors: (Bogdan Wojtsekhowski)
13.1 Congratulations to Bogdan for preparation of poster for DNP meeting.
13.2 Showed VDC drift spectra from Hadron arm detectors with
Argon/ethane. NO TAILS!
13.3 Cerenkov threshold settings discussed.
13.4 Preshower ADC spectra looked good but will require further fine tuning
of the HV.
13.4.1 Eddy notes problem that there is no map of which TDC goes
with which preshower counter.
13.4.2 Original plan was that there be no TDC’s. They weren’t
considered necessary.
13.4.3 At present the information doesn’t exist.
13.4.4 Need to assign a student to work on this.
13.5 Shower counter situation less clear. Bogdan requests runs with higher
energy beam to commission the lead glass system..
-JJL