E362 FD weekly meeting, 
R307, 96/08/27(Tues), 17:00-23:00,  
Present:Nishikawa(Chairman),Ishii,Chikamatsu,Sakai(INS),Kohama(Kobe),
        Etou(Tokai),Nakamura,Ohyama,Ishida,Sakuda(KEK)
        
(1) Muon chambers (Ishii/Chikamatsu)
*Check of the existing electronics boards for Barrel muons---1/3 finished
 by Tauchi. (The name, "Barrel" and "F/B", is just historical. There are ~400 
 modules of Barrel chambers and ~400 modules of F/B chambers.)
*Computer-controlled tension measurement is being tested by Inagaki/Shiino.
 It takes ~1min/wire. 
*Leak test of F/B chambers---19 sets out of 33 are done. (Chikamatsu/Ishii)
*Ishii tries to fix the leak around the Delrin feedthru using Silicon
 filling or glue.
*First draft of the specification document for the muon detector is
 written by Chikamatsu and handed to Nakamura(KEK).
*Taino/Sakuda checked the necessary jigs and parts for sending out muon
 filters from VENUS in early September.
* Our TKO memory modules were brought back to the electronics group 
 by mistake. Ishii found 8 modules there.  Ohyama will find the rest
 
(2)HORN subjects related to FD (Kohama)
Horn group asks if it is possible to make the diameter of the tunnel 
at the entrance smaller, say 1.25m, than the present design value, 1.5m.
If so, the design of the endplate becomes much easier and more reliable.

(3)Experimental hall (Nakamura)
Reports from each hardware group for specification document:
* Draft of muon detector structure is written by Chikamatsu.
* SCIFI structure and LG structure are summarized by Sakuda.
* Power consumption of the electronics system is reported by Sakai.

 Nakamura had the first meeting on excavation of the experimental hall
with Hazama Inc: 
* A cylindrical hall is cheeper than the rectangular hall.
* One big cylindrical hall with 25m diameter is hard and expensive. 
 They suggest two small cylindrical halls, one for 1kton tank and the other 
 for FG (Fine-Grain) detector. We ask ICRR if they have problems with the case.
* The structure and the installation method of the muon detector are quite 
  uncertain at this moment. He will talk with Mitui-shipbuiling Inc.

(4) SCIFI 
* Kurary measured the ageing effects (attenuation of light @500nm vs time)
 for various fibers (SCSF38/77,multi-clad/single clad) in air and in N2.
 It is known that the ageing manifest itself as the attenuation length of light
 becoming shorter. 
   Based on this report, Etou estimates the reduction of light 
 with propagation distance of 1m after 5 years: 
 For SCSF77M (SCSF38M), the reduction is only 3% (2%) at 25deg in air. If 
 SCSF38 is kept in N2, it is 0.01%. It looks evident that O2 is the cause 
 of the ageing effects. 
   Question was raised about using 500nm light. Sakuda commented that 500nm
 is not far off from the sensitive region of IIT. 
   Kurary will measure the ageing effects with our fibers "SCSF78M" in air and
 without O2.
   Kobe group will measure the ageing effects with SCSF78M in air and in N2
 too.  
* Oyama reports on the aluminum water cell from the meeting with Furukawa Co.
 We can buy 60mmx200mmx3000mm (2mmthick) cells inexpensively in a month or so.
 They can be used for beam test too. We will establish the strength and the
 structure using these cells.
* Fijino(KEK) shows the alternative design for the water cell. This will be
 tested too. 
* SuzukiAT(Kobe) discussed about the fiber-spooling machine for real detector
 with Kawai/Ishikawa (Nagoya). They say that the drum weight should 
 not be heavier than the present one. The design must be finished in October.
* Aluminum vapor will be attached to one end of the fiber-ribbons soon at
 Kawai-Optics Inc.
* Etou/Aoki/Sakai will start up the system of fiber-IIT-MCP-CCD-FADC-VME
 next week. The optimization must be finished in October.

(5) Electron identification in nu_e analysis
* Ishida shows several events from nu_e QE events as well as single track
 (pi0, pi+-) events. He will try to identify electrons and thus nu_e QE
 events using SCIFI detector. He will work with Nakamura and Chikamatsu.  
* Chikamatsu shows the study of electron/muon separation using the number 
 of hits of SCIFI. He says that he can reject muons if he requires
 more than 3 hits at one of layers along the track. 

(6) Discussion
 The FG design and the drum design depend much on the result of IIT
 optimization and simulation study. All R&D works must be integrated
 and converged by the end of October. Decisions on the design will be 
 made even if some of the items are uncertain.
// (Memo by Sakuda)