Minutes of Hall A Group meeting
August 12, 1997, 13:30

Update on Hall A run plan changes (K. DeJager):
	Fire in the Q3 Hadron arm power supply should be repaired by Wed, Aug 
13. Continue with Exp 89033 at 2445 MeV. The running has been extended by 2 days 
till 8:00 am, Wed, Aug 20. Discussion on the cause of the fire, damage to the 
actual Q3 magnet should be very small. Possible consequences: 2 days lost to 
installation. Rest of schedule remains unchanged. New Fall schedule available on 
the web.

J. McIntyre (EXP89033): 
	1. Basically finished pm = 140 MeV/c point  with 25 million counts.
	2. Get Moller some time: 6 hours commissioning.
	3. eP got couple of test runs (1 hour good data on second run).
	4. Beam Pol ~ 30%
	5. pm = 85 MeV/c point:	(i) H data: focal plane scan
				(ii) 16 hours for e-arm commissioning
				(iii) statistics: 5 million counts.
	
	then Power supply blew up, since then Hadron arm is surveyed.	
	will require 4 shifts: complete this point with 15 million counts.
	
	6. Exp89003 will take over and reposition both spectrometers.
	7. Kevin Fissum takes over as run coordinator on Wed, Aug 13 at 1:30 pm.
	8. More help needed for last 2 days and also for surveying over the 		
	weekend.
	
	End of Run Party after this meeting.
	
Ed Folts:
	1. rebuilt waterfall target last week
	2. Rebuilding Q3 power supply.
	3. Prepare for shutdown.
	4. Install raster table.
	
James Profitt:
	1. UPS system for hadron dipole.
	2. Interlock system for the magnet.
	3. Last Friday: unusual problem, serial controller on power supply was 		
	communicating wrong information. No errors came up.
	4. Q3 problem: circuits were bench tested again (same problem a year ago 	
	and they were tested then too).
	 		
Paul Brindza:
	Design continuing on pol. He3 target.
	Pointing system also underway.
	Cryo-line work on extension cables.
	Documentation on cryotarget.
	L. Cardman needs reminder to sign his reqs.
	
Alan Gavalya:
	Working on frame on aerogel
	
Bogdan W:
	1. Shower counter spectra (gas Cerenkov spectra) and Monte Carlo
	Number of photoelectrons larger by 20% (~9.5 photoelectrons)
	Phototube replaced. 
	Replace base from A type to B type to avoid saturation. Better agreement 	
	with expectation.
	2. Espace analysis: Robust techniques for analysis of gas Cerenkov.
	
J.P Chen
	1. Cryotarget
	Transport fixture fabricated. Technician setting it up.
	Solid target ladder being fabricated - ready by early next week.
	Target for fast raster - Arun sent it to machine shop. It has a 1mm and 	
	2mm square holes.
	JT control box alraedy completed.
	Target cells have been measured.
	More tests required to do before going into hall.
	2. Compton Polarimeter
	Three working group meetings last week. The topics were:
	Design for the magnets - Mark Wiseman.
	Optics and commissioning of the chicane.
	Slow controls.
	Next week: Big group from Saclay to go into details.
	L. Cardman: Chicane in for the January 1998 installation - look in 		
	schedule. Kees mentioned that it could be done in Feb, 1998.
	
A. Saha
	1. Discussion with Plant Engineering on 9th Dipole shed. There may be a 	
	cost increase on the shed.	
	2. eP took some data in the optics run.
	3. Coil pulsing did not occur.
	
M. Liang
	1. Waterfall target
	Encoder died, manual control. Empty target in position now, will move to 	
	waterfall target in next 24 hours.
	2. Work on batch farm.
	
A. Glamazdin
	Moller Polarimeter status
	1. Big differences with different orientations. This may be coming from 	
	wrong helicity signals, so changed software. Ran again , with eP target. 	
	Polarization down to 0. No more time. No temperature information. 
	Moller Polarimeter still not an easy device, need more time for 		
	understanding.
	Kees:	End result very unsatisfactory. Still need to estimate errors. 		
	0.5% for electronics. Target thickness error 0.2 microns. Other error 		
	sources.
	
Kees DeJager:
	1. Trailer City will have power outage Saturday. Phones may be affected.
	2. Estimate number of tapes for data analysis for experiments: 89003, 		
	89033, D(FF) ... Request from Computer Center and order them.
	3. PAC ratings for Hall A proposals.
	4. First measurement of FPP and polarized beam. Learning experience for 	
	future experiments. Another achievement for Hall A collaboration.		
	
C. Glashausser
	Thanks to everyone from 89033. Also thanks to Larry and Kees for 
support.