E362 FD weekly meeting 
At KEK R306, 96/06/25 (Tues), 10:00-12:20
Present:Nishikawa,Ishii,Chikamatsu,Sakai(INS),Sakuda(KEK),Etou(Tokai),
        Maruyama(Tohoku),Kohama(Kobe),Tamura,Nakamura(Niigata),
        Nakano,Yamaguchi(Okayama)
 
(1) Yamaguchi estimates the number of Cherenkov photons emitted in 4cm thick
water. He took into account the refractive index and the absorption 
coefficient (n,k) of water wrt wave length. He and Nakano will measure 
the reflectivity of Tyvek, Gortex and Al-Mylar using Monochrometer this week. 
They will present the result at JPS meeting at Saga (October 6-10).

(2) Etou shows the result of the light yield measurement of SCSF78 (0.5mmD,
0.7mmD)x(single clad, multi-clad). Multiclad fibers produce 50% more photo-
electrons than single clad fibers. He also measured BCF12. For example, SCSF78
multiclad fibers give 3 pe's at the distance of 3m.  For the beam test, 
6 sets of fiber sheets of the size 50cm x 1.5m x 4layers(xx,yy) 
will be made first. The rest of the fibers will be used for making 3m long
sheets. The details of the test will be reported by him next week.     

(3) Ishii reports the status of muon group. Tauchi analyzes the cosmic-ray 
data taken with real muon chambers. They modified the oscillator frequency
from 40MHz to 20MHz to match the beam gate (1 microsec).  He obtains the 
position resolutions of 1.8mm (40MHz) and 3.5mm (20MHz). The results are 
very much reasonable. Test modules for the preamps are working.
 Shiino designs the NIM module for tension measurement. They borrow a permanent
magnet from Belle group.
 Ishii and Chikamatsu design the procedure to test the muon chambers. 
All preamps for Barrel muon chambers are transferred to INS. 

(4) Kohama calculates the deformation and strain of the second horn under the
Maxwell force using ANSYS. He finds that the present design gives the stress 
much less than 3kgf/mm**2. The maximum stress occurs at the junction of the
shell. 

(5) Nakamura estimates the acceptance of nu_e +n ->e+p and nu_mu+n -> mu+p
for two realistic cases in which 2 segments of LG blocks and 3 segments 
are used. 2 segment case is as good as 3 segment case. 

(6) Maruyama shows the first version of the drawing for SCIFI structure 
written by Fujino(KEK mechanical engineering center). 

(7) All muon chambers and iron filters were removed from VENUS detector
as of June 28. 
 A new drum is now at Nagoya. Nagoya group (Nakamura et al) will set up
the fiber-winding machine next week. Aoki, Hara and Etou will meet Nakamura at
Nagoya on June 4. 

TV conference (KEK-Kamioka) is scheduled on July 2 (Tuesday).
// (Memo by Sakuda)