Weekly JLC Physics Group Meeting
Place: 3F Bldg 3, KEK
Time: 10:30, 97/05/09
0.1) General Notifications
0.2) Calorimeter R&D Status
 General Notifications
1.1) Budget (Miyamoto)
The 1997 budget for JLC R&D has been announced.
It is of very short string as more or less expected.
Anyway each subgroup is requested to prepare a budget
execution plan and hand it to Miyamoto by May 15.
1.2) Mailer Machine (Miyamoto)
The computer center is planning to migrate the mail handling
operation to a new workstation from KEKVAX.
KEKVAX will be gone eventually upon completion of this
KEKVAX users are recommended to move timely.
---> Some potential problems were pointed out at the meeting.
One is the mail storage space on the new machine
and the other is the internet address since KEKVAX
has been so popular.
1.3) New faces
A lot of new students joined the CAL subgroup!
Their names and picutures will be available from
the CAL Home Pahge.
 Calorimeter R&C Status
2-1) HPD Simulation (Kanaya)
It was found that the LED light source used to measure the
uniformity of the HPD responce had itself some non-negligible
Simulation based on electrodynamics for photoelectrons in the
HPD reproduces the data well when empirical 10% gain increase
is taken into account.
2-2) Beam Test Data Analysis (Suzuki)
Beam contamination is under study employing TOF information
from trigger counters. 1 GeV data show no significant
difference for electron- and pion-trigger samples.
The resolution is limited by the fact that the trigger
counters are of single-end readout type. Time-walk
correction is yet to be applied, though.
Suzuki is now investigating the deviation from a gaussian
shape of the observed pulse height distributions.
The observed tail toward higher pulse height region might
be simply from non-gaussian statistics (Poisson?) or from
beam contamination. More studies are necessary to draw
any solid conclusions.