1. SciFi Tracker Beam Test outline The performance TOF which is needed to Beam Test & Guide7 Simulation TOF calculation TOF ACC estimation test for Beam Test @KEK Atsushi Horikoshi, Osaka-U

2. phase Ⅰ :estimate of basic SciFi tracker performance particle tracking w/magnetic field, detection efficiency, high beam rate performance phase Ⅱ :detailed test low momentum μ(300 ～ 400MeV/c) detection, reconstruction of emittance ’ 05 Beam Test : SciFi Tracker test schedule

3. Phase Ⅰ setup （ Apr 2005, KEK pi2 ） 5x5 hodoscpe

4. to estimate longitudinalμmomentum, SciFi tracker is put in magnetic field magnetic field ： superconducting magnet, Super-JACEE(1T) L Phase Ⅰ： particle tracking in magnetic field

5. Phase Ⅱ setup (Oct 2005, KEK pi2) ・ μmomentum ： 300~400MeV /c ・ low beam rate ・ but, defuser makes many condition of beam

6. TOF timing resolution to devide pi & μ π-μ PID @ sigma=50ps ・ ~700MeV/c PID>3σ ( >99.7% ) ・ 1GeV /c PID=1.65σ ( >95% ) Phase Ⅰ (high rete@~1GeV) σ<50ps needed ! π ２ beamline ： μ,e,π,p ⇒ we want to select μ momentum(MeV/c) TDC(ns)

7. shape of TOF 400 392133 20 80 unit : mm ・ very long light guide ⇒ to avoide strong magnetic field ・ PMT:R6504S fine mesh PMT (used by BESS, 19DY, strong resistance of magnetic field)

8. S-JACEE side view magnetic field @TOF PMT ３０００ GAUSS TOF shape requirement

9. magnetic field @TOF PMT ⇒ PMT direction is parrarel to magnetic field

10. TOF shape requirement magenta : scintillator length : 40cm long light guide : 50cm front view : isotropical position ⇒ same magnetic field ・ long light guide : lower resolution (60ps) near to SciFi tracker It is easy to make isotropical poistion ・ short light guide : high resolution (50ps per counter) but, design of light guide is very difficult we selected long TOF

11. guide7 Simulation timing resolution beam@center of counter 64.59ps per PMT If PMT resolution is same, σ(counter)=1/1.41σ(PMT) ⇒ 45.80ps per counter

12. TOF & ACC estimation testπ ２ Beam Line(KEK) ’ 05 2/1~2/7 done define beam position of TOF ・ coincidence with ref1 & ref2 ・ coincidence with ref1 & cube ref 1 & ref 2 : 100mm x 5mm(t)

13. TOF construction scintillator & light guide is wrapped by Aluminized Mylar(50μmthin) scintillator EJ230(BC420) EJ204(BC404)

14. ACC construction 10PMTs used acc index : 1.03

15. beamline setup right: ref1&ref2 down:beamline setup

16. estimation of the resolution(preliminary) TOF1rt-TOF1lt ⇒ effect of external counter of sigma is eliminated @ center of counter σ=1.662count 28.8ps/count ⇒ 47.8ps Guide 7 Simulation 45.8ps

17. measurement of resolution(preliminary) all plots are time walk calibrated

18. position dependence of resolution (preliminary) good resolution~ 50ps @all pos

19. summary We performed TOF & ACC estimate test @ pi2 beam line, in feb1st~feb7th TOF timing resolution is sufficiently to distinguish pion calculated resolution is ~ 50ps