PWO/APD Activities at Hiroshima U. Kenta Shigaki (Hiroshima University) 20 July 2004 at CERN

PWO/APD Activities at Hiroshima U. - Kenta Shigaki2 20 July Presentation Outline - Recent Activities on PWO/APD at Hiroshima  continuing property studies of key components  better expertise on PWO/APD handling cooling noise reduction  calorimeter prototype performance evaluation beam tests at KEK-PS and Hiroshima-REFER  readout electronics design update (Toru) Summary and Outlook

PWO/APD Activities at Hiroshima U. - Kenta Shigaki3 20 July Past PWO Crystal Property Studies - Furukawa Co. Ltd. in Tokyo, Japan density 8.28 [g/cm 3 ] radiation length 0.89 [cm] Moliere radius 2.2 [cm] peak emission [ns] refractive index x 20 x 200 mm Y-doped PbWO 4 light yieldmean decay time transmittance measured with Hitachi U3010 spectrophotometer ALICE-PHOS operation point ALICE-PHOS operation point

PWO/APD Activities at Hiroshima U. - Kenta Shigaki4 20 July Recent PWO Crystal Property Studies - RI&NC Co. in Minsk, Belarus  adopted by CMS  investigated; similar properties as Furukawa’s ref. graduation thesis by K.Yokoyama (available only in Japanese) North Crystal Co. in Apatity, Russia  adopted by ALICE-PHOS  detailed investigation ongoing at Hiroshima further comparison of crystals in progress

PWO/APD Activities at Hiroshima U. - Kenta Shigaki5 20 July Expertise on PWO/APD Handling - cooling with Peltier modules  stable operation down to ~ 0 ºC better ground handling to reduce noise  successful operation of APD readout system

PWO/APD Activities at Hiroshima U. - Kenta Shigaki6 20 July Prototype Performance Evaluation -  prototype components PWO crystals: Furukawa (Japan) / RI&NC (Belarus) / North Crystal (Russia) PMT: Hamamatsu R1450 APD: Hamamatsu S8664 pre-amplifier: Hiroshima ver.1/2 cooling: Peltier modules  tests in Japan Tohoku-LNS (2002); photons at 0.8 – 1.2 GeV Hiroshima-REFER (2003/04); electrons at 150 MeV KEK-PS (2004); electrons at 0.5 – 2 GeV

PWO/APD Activities at Hiroshima U. - Kenta Shigaki7 20 July Past Beam Tests at LNS/REFER - w/ PMT readout   E /E = 2.5 %/  E [GeV]  1.3 %   x = 2.3 mm/  E [GeV] noise problem with APD at room temp. counts [a.u.] E total = 141 MeV σ/E total = 7.3 % = 2.8 % /  E total energy [MeV]

PWO/APD Activities at Hiroshima U. - Kenta Shigaki8 20 July Recent Beam Test at KEK-PS - prototype w/ real ALICE-PHOS components  NC PWO + Hamamatsu APD electron enriched non-separated (IT) beam  negatively charged  electron/beam ~ 1 % before online enrichment beam momentum scan  0.5 GeV/c – 2.0 GeV/c APD HV scan  380 – 430 V (400 V nominal)

PWO/APD Activities at Hiroshima U. - Kenta Shigaki9 20 July KEK-PS T564 (16-23 June 2004) M total (mixed) triggers; including 664 K electron triggers successful operation of APD readout

PWO/APD Activities at Hiroshima U. - Kenta Shigaki10 20 July PWO/APD/Readout Signals - ADC distributions punch-through hadrons electrons pre-amp output shaping amp output

PWO/APD Activities at Hiroshima U. - Kenta Shigaki11 20 July Hiroshima’s Prototype Performance -  E /E = 5.5 % at 1 GeV/c, 3.1 % at 2 GeV/c  with quick and rough near-line calibrations  including significant beam momentum spread analysis ongoing to subtract external contributions gas cherenkov hit required electrons in center cell selected

PWO/APD Activities at Hiroshima U. - Kenta Shigaki12 20 July cf. Kurchatov’s Prototype Performance - Kurchatov 16  16 prototype   E /E at –25 ºC : 1.3 %/E [GeV]  3.6 %/  E [GeV]  1.1 %

PWO/APD Activities at Hiroshima U. - Kenta Shigaki13 20 July Summary and Outlook - continuing basic property investigation of key components (PWO/APD/readout) several prototypes fabricated/tested better local expertise independent prototype performance evaluation in progress

PWO/APD Activities at Hiroshima U. - Kenta Shigaki14 20 July Official Business - applied for ALICE associate collaboration  together with Tokyo and Tsukuba Universities  approval requested at next ALICE meeting  “official” PHOS participation expected soon

PWO/APD Activities at Hiroshima U. - Kenta Shigaki15 20 July PHOS Collaboration at Hiroshima U. - 3 staffs, ~10 graduate students  H.Harada, K.Haruna, K.Hirashita, K.Homma, K.Hosokawa, R.Kohara, Y.Nakamiya, M.Ouchida, H.Sakata, K.Shigaki, T.Sugitate, D.Toyoda, Y.Tsuchimoto, K.Yokoyama Hiroshima PHOS web page 