PWO/APD/CSP Development at Hiroshima U.

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PWO/APD/CSP Developmentat Hiroshima U.

• Hiroshima ALICE-PHOS Group
• (T.Sugitate, K.Shigaki, et al.)
• 17 August, 2004, at CERN

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- Presentation Outline -

• Recent Activities on PWO/APD/CSP at Hiroshima
  University
• readout electronics status update
• CSP design version 3
• continuing property studies of key components
• better expertise on PWO/APD handling
• calorimeter prototype performance evaluation
• beam tests at KEK-PS and Hiroshima-REFER
• Summary and Outlook
• Official Business

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- Pre-amplifier Design Revised (Ver.3) -

• slightly modified layout (see next slide)
• no circuit change from version 2
• proposed and discussed in July, 2004
• version 3 status and plan
• 100 boards in production
• delivery expected in late-September, 2004
• 50 of them w/o capacitor C5 mounted
• to decouple test input pin from signal lines
• to be sent to Iouri at CERN for evaluation
• shipping planned in October, 2004

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- New Pre-amplifier Layout (Ver.3) -

• version 3 mask (black) overlaid on
  version 2 photo (green)
• components moved (from yellow to red) to make
  space around APD soldering holes

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- Pre-amplifier Task and Schedule -

• early decision of CSP version required
• version 2 or 3 on 1st PHOS module ?
• need to complete mass production in JFY04 (ending
  March, 2005)
• CSP for 1st PHOS module coming soon
• to be ready for assembly by late-January, 2005

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- Past PWO Crystal Property Studies -

• Furukawa Co. Ltd. in Tokyo, Japan

density 8.28 g/cm3 radiation length 0.89
cm Moliere radius 2.2 cm peak emission
420-440 ns refractive index 2.3
Y-doped PbWO4
transmittance measured with Hitachi U3010
spectrophotometer
20 x 20 x 200 mm
ALICE-PHOS operation point
ALICE-PHOS operation point
light yield
mean decay time
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- Recent PWO Crystal Property Studies -

• RINC Co. in Minsk, Belarus
• adopted by CMS
• investigated similar properties as Furukawas
• 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

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- 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

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- Prototype Performance Evaluation -

• prototype components
• PWO crystals Furukawa (Japan) / RINC (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

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- Past Beam Tests at LNS/REFER -

• w/ PMT readout
• sE/E 2.5 /?E GeV ? 1.3
• sx 2.3 mm/?E GeV
• noise problem with APD at room temp.

counts a.u.
Etotal 141 MeV s/Etotal 7.3 2.8 /?E
total energy MeV
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- 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)

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- KEK-PS T564 (16-23 June, 2004) -

• 31.3 M total (mixed) triggers
• including 664 K electron triggers
• successful operation of APD readout

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- PWO/APD/CSP/Readout Signals -
ADC distributions
pre-amplifier output
punch-through hadrons
electrons
shaping amplifier output
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- Hiroshimas Prototype Performance -

• sE/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

electrons in center cell selected
gas cherenkov hit required
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- cf. Kurchatovs Prototype Performance -

• Kurchatov 16?16 prototype
• sE/E at 25 ºC
• 1.3 /E GeV ? 3.6 /?E GeV ? 1.1

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- Summary and Outlook -

• charge-sensitive preamplifier (CSP) design
  revised version 3 in test production
• CSP for 1st PHOS module by January, 2005
• continuing basic property investigation of PHOS
  key components (PWO/APD/readout)
• several prototypes fabricated/tested
• better local expertise
• independent PHOS prototype performance evaluation
  in progress

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- Official Business -

• applied for ALICE associate collaboration
• together with Tokyo and Tsukuba Universities
• approval requested at next ALICE meeting
• official PHOS participation expected soon

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- 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
• http//www.hepl.hiroshima-u.ac.jp/quark/pwo/