Yonsei – Tsukuba Workshop ／ Hiroshi Tsuruoka ／ Aug 22 2001

1. Yonsei – Tsukuba Workshop ／ Hiroshi Tsuruoka ／Aug 22 2001 Current Status of TOF Analysis １．PHENIX実験とは ２．なぜ新たな検出器が必要か？ ３．Time Zero Counter の設計 ４．テスト実験（KEK） ５．まとめ １

2. Yonsei – Tsukuba Workshop ／ Hiroshi Tsuruoka ／Aug 22 2001 TOF Performance CERN WA98 (1996) PHENIX TOF (Dec 2000) Tsukuba-Yonsei Workshop By Akio Kiyomichi σ<110ps s ~ 85ps We want to understand the contents of 110psec time resolution. • New calibration parameter • Another cause • Cable length , FEM jitter ２

3. Yonsei – Tsukuba Workshop ／ Hiroshi Tsuruoka ／Aug 22 2001 New Calibration Parameter Dec , 2000 Aug , 2001 9 TOF parameter set 9 TOF parameter set Update ! • Time offset • Slewing parameter • Y position offset • Light velocity in scint. • Energy loss conversion factor • Time conversion factor • Charge conversion factor • TVC/QVC pedestal • Global Time offset ( still 0 value ) • Time offset • Slewing parameter • Y position offset • Light velocity in scint. • Energy loss conversion factor • Time conversion factor • Charge conversion factor • TVC/QVC pedestal • Global Time offset Update ! Update ! Update ! Update ! By Akio Kiyomichi BBC parameter set BBC parameter set No Run dependence Checked Run dependence By Takashi Hachiya (Univ. of Hiroshima) ３

4. Yonsei – Tsukuba Workshop ／ Hiroshi Tsuruoka ／Aug 22 2001 Example. Slewing Correction Update Old（DSTv03） New（DSTv05） Timing[ns] Timing[ns] QVC[ch] QVC[ch] Spread • Problem in v03: • Slewing curve is weak by effect of attenuation. • for DSTv05 • Select hit region on scintillator. • To compensate for low statistics, add 32 PMTs with • PMT Gain correction & Timing adjustment Fitting function: y = A + B/sqrt(x) 6cm PMT |Track_projection - slat_center| <3cm 64cm Akio KiyomichiAnalysis meeting@BNL Aug 2 2001 ４

5. Yonsei – Tsukuba Workshop ／ Hiroshi Tsuruoka ／Aug 22 2001 TOF Performance For Year-1 used data : run11011 - 11775 cut criteria : • centrality 0-5% [cent == 0] • dch_quality == 23 or 31 • eloss > 2MeV • dR < 2 sigma (matching cut) • |tofz|<50cm && tofy>-100cm • (panel 3 or 4) Timing[ns] • Year-1 Time-of-flight resolution < 100ps. Momentum [GeV/c] Akio KiyomichiAnalysis meeting@BNL Aug 2 2001 ５

6. Yonsei – Tsukuba Workshop ／ Hiroshi Tsuruoka ／Aug 22 2001 Another Cause worsen resolution • Cross talk on FEM board • several hits on slat cross talk ! ALL 501event 96 ± 5 ps No cross talk 462event 97 ± 5 ps Clean hit only 341event 89 ± 7 ps several hits TOF – L／（c・β）[nsec] clean hit ! • A cut of clean hit only is effective ! Cut Criteria : Run11011-11775,cent[0-5%],Q=23or31,eloss>2MeV,dR<2sigma,1.4<p<1.8MeV,TOF Panel 1,3and4 ６

7. Panel 3or4 , Run#10758-11775 Panel 3or4 , Run#11011-11775 Panel 1or3or4 , Run#11011-11775 Panel 1or3or4 , Run#10758-11775

8. No Cross Talk Cross Talk Clean Hit Only < 2 Hits

9. Yonsei – Tsukuba Workshop ／ Hiroshi Tsuruoka ／Aug 22 2001 37m Cable + FIFO (PHENIX) or NONE(WA98) North South ①　～WA98 TOF FEM TOF FEM FIFO σ～42ps ③ ② ～3300 ② BBC TM ① ①BBC TM ========================⇒TOF FEM(N) ②BBC TM⇒TOF(S)side======⇒BBC side⇒TOF FEM(N) ③BBC TM⇒TOF(S)side⇒FIFO⇒BBC side⇒TOF FEM(N) σ～50ps ～3000 ③　～PHENIX • TVC=3300[ch] is the dynamic range which we can measure a particle of beta=1.   • FIFO works as discriminator module. • A 37 meter long cable worse resolution a little. σ～47ps ～3270 TVC[ch] ７

10. Yonsei – Tsukuba Workshop ／ Hiroshi Tsuruoka ／Aug 22 2001 The Jitter between TOF and BBC ８

11. Yonsei – Tsukuba Workshop ／ Hiroshi Tsuruoka ／Aug 22 2001 Jitter ９

12. Yonsei – Tsukuba Workshop ／ Hiroshi Tsuruoka ／Aug 22 2001 20nsec delay cable problem Year-1 Year-2 ~1500ch ~ 2200ch １０

13. Yonsei – Tsukuba Workshop ／ Hiroshi Tsuruoka ／Aug 22 2001 Appendix Online Monitoring By Kuroki １１

14. Yonsei – Tsukuba Workshop ／ Hiroshi Tsuruoka ／Aug 22 2001 ５．まとめ １２