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Hybrid PMT Tests & Geometry. Zisis Papandreou Detector Interface Meeting Bloomington, Indiana November 1 st , 2001. BCAL Dimensions (CDR). Length: 4 m Outer Radius: 90 cm Thickness: 20-25 cm (~16X 0 ) Pb Radiation Length: 1X 0 = 0.56 cm No. of modules: 48 (96 phi slices)
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Hybrid PMT Tests & Geometry Zisis Papandreou Detector Interface Meeting Bloomington, Indiana November 1st, 2001
BCAL Dimensions (CDR) • Length: 4 m • Outer Radius: 90 cm • Thickness: 20-25 cm (~16X0) • Pb Radiation Length: 1X0 = 0.56 cm • No. of modules: 48 (96 phi slices) • No. of PMTs: 12 x 48 = 576
A tight squeeze! KLOE Winston Cones – Module-0
HPMT New Geometry (10 PMTs)? Tough-cookie design! Solution: DEP redesigns the electronics housing
What’s a Hybrid? • Proximity-focused vacuum tube • Fast rise- and fall-time (2, 12 ns) • High QE for UV, Gain is 105 • Insensitive to high magnetic fields HV: -8kV Bias: -80V Pre-amp Shaper Fused silica window
The real McCoy… DEP PP0100Z UofR HVregulator DEP PP0350G
Preliminary HPMT tests • Discharging problem: partly solved • Pre-amp selection: solved • Signals observed from radioactivity source using a NaI detector • Direct communication with DEP established • Personnel: • Electronics engineer, technician, postdoc (Vitaly Kovaltchouk)
Regina “Flasher” • Was recently apprehended. • Replacement: • Optitron Xe-N Flasher System • 200 psi • 20 kV across the electrodes • Pulse resembles scintillator pulse • Externally triggered, frequency controlled, or single flash modes
HPMT Testing Chores • Need to perfect the electronic circuit • Fast charge pre-amp • Suitable pulse shaper • HV-rated cables • Communicate with DEP • Modify the detector design • Transfer knowledge • Bench tests • Operate with Flasher • Operate with Cosmic Rays
HPMT Geometry List • Optimize area reduction (4:1) • Light guides and Winston Cones • HPMTs must be staggered for clearance • No. of HPMTs must be settled • GUIDEIT MC simulations required • Good neighbor policy: • Solenoid • Drift chambers