Minutes of the E895 meeting
                  Graduate Chemistry Rm 403, SUNY Stony Brook
                               Monday 7/17/95

Attending:  GR - Gulshan Rai
	    RL - Roy Lacey
	    JA - John Alexander
	    BC - Brian Cole
	    SG - Steven Gushue
	    MG - Mark Gilkes
	    AJ - N. Ajitanand
	    HH - Hiro Heijima
	    PC - Paul Chung
	    JL - Jerome Lauret
	    EL - Erwan LeBras
	    TM - Tatiana Magda
	    RS - Rulin Sun
	    JB - Jacques Bouffety
	    MS - Meena Srivastava

Gulshan Rai described the events of the past week.

TPC:

The TPC is now out of its shipping crate and sitting inside the clean room on
top of its scissor table.  The water manifold is being reconnected.  All the
ferrules on the individual water lines are being replaced.  The water
recirculator will be hooked up, possibly with BNL standard 1-1/4" hose with
quick disconnects, rather than the LBNL standard 1-1/2" hose.

Someone will be needed to check all HV sections for leakage current while the
TPC is under nitrogen.  The fans in the clean room are kicking up dust from the
floor and need to be replaced with the blower/air conditioner before the gas
containment vessel can be opened for inspection, and the cathode plate can be
put back in place above the field cage.

The fiber optic cables will be tested this evening.  The final decision on the
direction of loading the magnet into the TPC is to be made on Wednesday.  The
magnet mapping starts on the 24th at 1.0, 0.75 and 0.5T to within ~5 gauss,
which is the limit of the ADC.

Gulshan and Hiro will complete the water manifold connections tomorrow.  MG,
EL and RL volunteered to test the gating grid driver and all associated power
supplies at Stony Brook.

Beamline:

Columbia will construct identical S1 and S2 counters.  Fast Hamamatsu 2081
PMTs would be ideal for this application.  The Cerenkov radiator will have a
scintillator as its backup.

The AGS says that there should be no appreciable beam steering, but low energy
beams may behave differently.  The question is whether retractable wire
chambers would be useful to E895 for beam diagnostics.

BC - We would need only two 2-plane chambers.  Less than the 6-plane chambers
     used at the AGS.

GR - Are they read out by CAMAC ?  If so, this could interface with our DAQ.

BC - Yes.  Vince, Ron and two students at Nevis will write the code.

JA - Why six planes in each chamber ?

BC - Left/right ambiguity.  Can do relatively accurate tracking.

GR - At the Bevalac, we had 1mm resolution from the PLUTOS.  But we didn't
     correct event-by-event in the flow analysis - we used an average beam
     angle.

JA - Without the PLUTOS, will there be provision to do the event-by-event
     corrections ?

BC - Two planes should be adequate.

GR - E910 will use these chambers.  Should we build it in for E895 from the
     start ?  We brought WCs from LBL... we might not have to build anything.

BC - What kind of cathodes ?

GR - Flashed mylar, and also mylar windows.

GR - AGS and LBL experts say that there is no steer in the beam.

GR - AGS PWCs are in-air.  We don't want air upstream of the TPC where we can
     avoid it.  ~300-400 interactions in a meter of air per spill, for a 3000
     beam particle spill.  That's comparable to a 5% target.

JA - How far apart will the chambers be ?

BC - We plan on 1-2 meters.

JA - We could pull out the downstream one.

GR - We should put both WCs upstream of the last veto.  We don't want them
     to be close to the target.

SG - If they were further upstream, we'd have a better lever arm.

GR - We need to decide whether we'll go with the chambers that already exist,
     or the ones E910 will build.  The existing ones SG and I can locate from
     Harvey Gould.

GR - Gerry Bunce and Dana Beavis will help with the beam tune.  During the full
     energy heavy ion run, we don't get beam in the A1 line and will use that
     time for testing and debugging.  Also it will take a few days for the low
     energy beam to get to us after the full energy run ends.

SG - A 10**3 spill will be tough for the AGS to deliver.  They need 10**9 in
     the machine even to see signals on their monitors.

GR - The beam will be defocused and collimated.  We'll need feedback from the
     MPS to the AGS control room put in place.

SG - We have to keep track of the stripping foils used in the tandem.  Each
     foil has a lifetime of 45 min - 3 hrs.  If enough of them have been burnt
     up in a previous run, there may not be enough for our run.  There has to
     be a period between runs to replace foils - it's a big job, and there can
     be problems.

GR - Target assembly ?

MG - We now need to nail down the dimensions and draw it up.  Paul has been
     working with AutoCAD for this purpose.

BC - It might be nice to incorporate a table extending into the re-entrant,
     on which other elements could be placed. 

GR - Simulations ?

MG - I am incorporating Xihong's code.  I will contact Thomas Wienold for his
     code.  Hopefully, some results by the next meeting.

GR - Heng Liu arrives in a few days, for a month.  He'll set up the high
     voltage control for the beamline and detectors.

GR - Next week, we'll also discuss progress on EOS physics.


Prepared by: Mark Gilkes