Development of 144 Channel Multi-Anode HPD Development of 144 Channel Multi-Anode HPD for Belle Aerogel RICH Photon Detector for Belle Aerogel RICH Photon Detector 1 I. Adachi, 2 R. Dolenec, 2 A. Petelin, 3 K. Fujita, 2 A. Gorisek, 3 K. Hara, 3 D. Hayashi, 3 T. Iijima, 3 K.Ikado, 4 H. Kawai, 5 S. Korpar, 3 Y. Kozakai, 6 P. Krizan, 4 A. Kuratani, 3 Y. Mazuka, 7 Y. Miyazawa, 1 S. Nishida, 8 I. Nishizawa, 9 S. Ogawa, 2 R. Pestotnik, 8 T. Sumiyoshi, 4 M. Tabata, 3 M. Yamaoka 1:IPNS, KEK, Tsukuba, Japan / 2:J.Stefan Institute, Ljubljana, Slovenia / 3:Dept. of Physics, Nagoya Univ., Nagoya, Japan / 4:Dept. of Physics, Chiba Univ., Chiba, Japan / 5:Faculty of Chemistry and Chemical Engineering, Univ. of Maribor, Maribor, Slovenia / 6:Faculty of Mathematics and Physics, Univ. of Ljubljana, Ljubljana, Slovenia / 7:Dept. of Physics, Tokyo Univ. of Science, Noda, Japan / 8:Dept. of Physics, Tokyo Metropolitan Univ., Hachioji, Japan / 9:Dept. of Physics, Toho Univ., Funabashi, Japan presenter: Ichiro Adachi ([email protected]) Aerogel radiator Position sensitive PD with B=1.5Tesla Cherenko v photo n 200mm n=1.05 Proximity Focusing RICH with Aerogel Radiator Developed for new particle ID device in the Belle fo rward region • extend /K separation capability up to 4 at 4.0GeV/c • limited space • operational under 1.5 Tesla magnetic field Key elements • Hydrophobic aerogel with refractive index of 1.050 as a Cherenkov radiator • Position sensitive photodetector with ~5x5mm 2 pixel size • Electronics for read-out The present Belle detector Principle of Operation Established at Test Beam Experiments n=1.05 aerogel radiator =14mrad Npe = 6 4 separation confirmed 4.0GeV “K”4.0GeV typical event RICH prototype counter Hamamatsu Multi-anode Flat-Panel PMT(H8500) /K 4 separation at 4 GeV/c achieved with a prototype co Multi-Anode Hybrid Photon Detector : Key Component • High sensitivity to single photon • Immune to 1.5 Tesla magnetic field • Large effective area Basic requirements ybrid (Avalanche) photon detector is our first candidate eveloped with Hamamatsu Photonics Package 72x72 mm 2 # of pixels 12x12(6x6/ chip) Pixel size 5x5 mm 2 Effective area 64 % HAPD specifications 1 diode chip pixel ated to 6x6 channe ls 72mm 72mm = “bombardment” gain ~1000 x “avalanch e” gain ~10 single photon signal ~10000 electrons ceramic tube Experimental Set-up and Noise Level Protector H.V 144Ch HAPD PreAmp Shaping Amp MCA Pulse Generator Light Shield Box PC LED C oaxial cable Cathode A node Bias G uard ClearPulse 5 80K ClearPulse 4 417 Amptek pocketMC A 150pF 100MΩ 220MΩ 220MΩ 222pF 222pF 10MΩ High Voltage Bias Voltage Reverse bias voltage supplied to cathode Signal extracted from anode side LED used as a light source Only 1 channel read out, Others floated Bias_scan 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 0 50 100 150 200 250 300 350 400 reverse Bias voltage chipA chipB chipC chipD Bias_scan 500 700 900 1100 1300 1500 1700 1900 2100 0 50 100 150 200 250 300 350 400 reverse Bias voltage[V] chipA chipB chipC chipD Noise level check by bias voltage scan Full depletion observed at ~50V Minimum noise level ~ 280V Similar tendency for all of 4 chips Diode chips show reasonable behavior Pulse Height Spectra HAPD Response for single photon light pedestal 1 p.e. Clear signal observed pedestal 1 p.e. 2 p.e. 3 p.e. 4 p.e. 5 p.e. 6 p.e. 7 p.e. Response for multiple photon light Total gain ~7,320 S/N ~ 4.9 Chip-A ch#22HV= -8.5kV & Bias=+319V QuickTime˛ Ç∆ TIFFÅià≥èkǻǵÅj êLí£ÉvÉçÉOÉâÉÄ Ç™Ç±ÇÃÉsÉNÉ`ÉÉÇå©ÇÈÇΩÇ Ç…ÇÕïKóvÇ≈Ç ÅB fl ∑ ChipA ChipA ChipD ChipD ChipC ChipC ChipB ChipB Target : ch22 - Bias=+340V - Gain 〜 7,360 - S/N 〜 4.8 - Ava. Gain 〜 4.8 Target : ch22 - Bias=+340V - Gain 〜 8,130 - S/N 〜 4.5 - Ava. Gain 〜 5.6 Target : ch22 - Bias=+360V - Gain 〜 8,530 - S/N 〜 4.1 - Ava. Gain 〜 5.7 Target : ch22 - Bias=+319V - Gain 〜 7,320 - S/N 〜 4.9 - Ava. Gain 〜 4.4 We can observe single p.e and S/N ratio is larger th an 4.1 in all 4 chips. H.V=-8.5kV Uniformity & X-talk in Diode Chip A B C D 10 5 gle photon-equivalent light injected for all channels in one diode chip-A Uniformity of c 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 1 6 11 16 21 26 31 36 # of chan 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 11.00 total gain Noise S/N Gain Gain Max Max 〜 〜 7,700@ch16 7,700@ch16 Gain Gain Min Min 〜 6,310@ch31 6,310@ch31 S/N S/N Max Max 〜 〜 6.2@ch8 , 21 6.2@ch8 , 21 S/N S/N Min Min 〜 〜 4.3@ch6 4.3@ch6 Noise av Noise av 〜 1,310[e] 1,310[e] Single p.e. can be observed for all channels (except for #5 and #10) Gain ~ +/- 9%, S/N >~ 4.3, Noise ~1,300e Channel # Gain/noise/S-to-N ratio calculated for each channel Basic Properties for 4 Diode Chips from Our Measurements Ch17 Ch17 Ch16 Ch16 Ch15 Ch15 Ch23 Ch23 Ch22 Ch22 Ch21 Ch21 Ch29 Ch29 Ch28 Ch28 Ch27 Ch27 LED off 6 12 18 24 30 36 5 11 17 23 29 35 4 10 16 22 28 34 3 9 15 21 27 33 2 8 14 20 26 32 1 7 13 19 25 31 Spot@ch22 □2mm×2mm LED on LED light illuminated to ch#22 through a small spot Investigate pulse activities in neighbor channels for LED on/off Negligibly small contrib ution in X-talk activiti es Ch17 Ch17 Ch16 Ch16 Ch15 Ch15 Ch23 Ch23 Ch22 Ch22 Ch21 Ch21 Ch29 Ch29 Ch28 Ch28 Ch27 Ch27 Conclusions References We have developed a 144 channel multi-anode hybrid photon detector for a photo-sensor in the Belle aerogel RICH counter. New test sample delivered around the end of 2006 from HPK. Fundamental properties have been e xamined in our test bench. Clear signal from single photon light has been observed, and total gain of ~7,500 was obtained. Reasonable uniformity of gain and signal-to-noise responses found X-talk seems to be small 1. T.Iijima et al., NIM A543(2001)321. 2. T.Matsumoto et al., NIM A521(2004)367. 3. T.Iijima, S.Korpar et al., NIM A548(2005)383. 4. I.Adachi et al., NIM A553(2005)146. 5. P.Krizan et al., NIM A565(2006)457. QE = 24% from HPK measurement Avalanche gain calculated by total gain from our measurement and bombardment gain from HPK shee Delivered at the end o f 2006 after technical improvements in HPK pr oduction process except for noisy channels of #5 & #10