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Plug Shower Maximum Detector for CDF Run II. Alon Attal University of California Los Angeles - CDF Calor2002. Outline. Introduction Design Calibration Performance Conclusions. Intro to CDF Shower Maximum Detector. Purpose EM shower position measurement
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Plug Shower Maximum Detector for CDF Run II Alon Attal University of California Los Angeles - CDF Calor2002
Outline Introduction Design Calibration Performance Conclusions
Intro to CDF Shower Maximum Detector Purpose • EM shower position measurement • Distinguish EM / Hadronic showers Detector Properties • Scintillating strip / wavelength shifting fiber detector • 2 layers • 6400 5mm wide strips • Embedded ~6 radiation lengths into EM cal • 1.1 < |h| < 3.5 Endplug cross section (top half)
Criteria Strip layout with following properties: Maximize granularity Maximize fiducial volume Light yield at least 1 photoelectron/MIP Understand strip response to < 10% Solution Scintillator: Bicron BC408 WLS Fiber: Kuraray Y11-350 ppm PMT: Hamamatsu R5900-M16 3 pe/MIP Achievable with moving radioactive source calibration Design: Criteria and Solution Crossing Angle = 45°
Multi-Anode Phototube (MAPMT) Hamamatsu R5900M-16 3rd generation MAPMT Desirable Features: Compact Low x-talk 416 used Low h gain: 5x105 High h gain: 1x105
Moveable Co60 source irradiates each strip. Test beam shows source to particle response well correlated. 3 iterations of strip sourcing Corrections MAPMT HVs Pixel to pixel gains Energy Scale Calibration Particle Response Source Response
Strip to strip energy consistent. Strip response consistent from run to run. Detector Consistency
Particle Identification Deposited energy is clustered if above threshold. Clusters from both layers combined to from electron / photon candidates. Position determined from energy centroid. Average Shower Profile Zge+e- Events Bumps at ±4 due to optical cross talk
Energy Correlation Energy from Shower Maximum and EM Calorimeter are well correlated. Plot flattens out due to: • Increased shower depth • MAPMT non-linearity Shower Maximum Energy (GeV) EM Calorimeter Energy (GeV)
Position Measurement Position matching ~1.5 cm limited by EM Calorimeter. Better matching achievable with implementation of forward silicon tracking. Position Comparison Between SM and EM Detectors Clusters Distance in h-f space
Conclusions CDF Endplug Shower Maximum Detector successfully incorporates new technology. Detector has shown to work reliably in hadronic colliders. Future improvements forseen.