Weekly JLC Physics Group Meeting
Place: BLDG 3, KEK
Time:  10:30, 97/04/11

[0] Agenda
   0.1) General Notifications
   0.2) CDC R&D Status and Plan for FY97
[1] General Notifications
   1.1) FY97 Budget (Miyamoto)
   	FY 97 budget request has been made to Iwata-san.
   	It is expected to be available by the end of this month.
   1.2) Norik san 
   	Norik san has come back and will stay at Tanashi branch
   	till August. He is going to work on the CDC R&D.
   	Then he is moving to KEK and continue the chamber work
   	for additional one year.

[2] CDC Group R&D Status and Plan for FY97 (Yamaguchi)
   2-1) Present Status
   	Analysis of cosmic ray test data is on going.
   	Some preliminary results include:
   	a) In the central part of the 4.6m test chamber, 
   	   the average spatial resolution is about 70 microns
   	   for both normal and inclined (45 degrees) incidence. 
   	   The number is a little bit misleading since the
   	   track distribution is not flat, sampling more in the
   	   small drift region where the resolution is good.

        b) The drift length dependence of the spatial resolution
           shows a quadratic increase towards the longer drift
           region, indicating deteriorating effects other than
           diffusion. Natural explanation for this is the pulse
           height drop due to electronegative gas such as O2,
           but this has to be confirmed.
        c) The z dependence is under study. The apparent spatial
           resolutions seem worse than those for the central part.
           This might be an artifact due to L-R ambiguity and
           requires more study.
        There were some discussions on the magnitude of the
        errors on the spatial resolutions of individual wires
        and the method to subtract the track extrapolation or
        interpolation errors. These points will be clarified
        in the next meeting.
   2-2) The goal of this year's R&D
        The R&D items include:
	a) Cosmic ray tests of the 4.6m chamber aiming at
	   more detailed investigations of dependence on z, angle,
	   and flow rate, etc.
	b) Test for stereo cells using 2 small test chambers 
	   mimicing central and end parts of the real 4.6m JLC 
	c) Improvement of readout electronics: preamplifiers,
	   in particular, considering impedance matching and
	   pulse shaping time.
	d) Wire material study to minimize creeping, or if
	   impossible, search for alternate design for endplates
	   and support cylinders to stand stronger tension total.
	   This study necessitates Monte Carlo simulations to
	   estimate effects on calorimetry.