Front-end Electronics for the ALICE Calorimeters

Journal Article · Sat May 01 04:00:00 EDT 2010 · Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment

OSTI ID:988257

Aamodt, K ^[1]; Awes, Terry C ^[2]; Enokizono, Akitomo ^[3]; Silvermyr, David O ^[2]; Zhang, Chun ^[4]; Young, Glenn R ^[2]; The, ALICE ^[5]

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1. University of Oslo, Norway
2. ORNL
3. Oak Ridge National Laboratory (ORNL)
4. University of Tennessee, Knoxville (UTK) & Oak Ridge National Laboratory (ORNL)
5. Collaboration affiliations

The ALICE calorimeters PHOS and EMCal are based on Avalanche Photo-Diode (APD) photosensors with Charge Sensitive Preamplifiers (CSP) for readout of the scintillating elements. The amplified signals are read out via 32-channel shaper/digitizer front-end electronics (FEE) with 14-bit effective dynamic range. The electronics is based on second order shapers with dual gain for each channel, getting digitized by ALTRO chips. Each APD channel is equipped with an individual 10-bit APD gain adjustment and 2 x 2 channel clusters generate a 100 ns shaped analog sums output (Fast OR) for the associated Trigger Region Units (TRU). The Fast OR signals are generated by first order shapers with a dynamic range of 12-bit given by the ADC in the TRU cards. Board controller firmware in the FPGA provides local monitoring and configuration of all parameters via the ALICE DCS system. The signal to noise ratio for MIP at 215 MeV is {approx}7 per channel with a noise level of 30 MeV at room temperature for a dynamic range of 80 GeV for PHOS, and the fast-OR RMS noise level is about 75 MeV for a dynamic range of 250 GeV for EMCal.

• Research Organization: Oak Ridge National Laboratory (ORNL)
• Sponsoring Organization: SC USDOE - Office of Science (SC)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 988257
• Journal Information: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Journal Name: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment Journal Issue: 40181 Vol. 617; ISSN 0168-9002
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
CALORIMETERS
DESIGN
ELECTRONIC EQUIPMENT
MONITORING
PHOTODIODES
PREAMPLIFIERS
READOUT SYSTEMS
SIGNAL CONDITIONERS
SIGNAL-TO-NOISE RATIO