NuMi Off-Axis Neutrino Appearance - NOVA Document Database ...

11. Reinforce the systems engineering team at the project management level for control
of interfaces.
12. Evaluate filling operations for static electricity hazards.
13. Develop a more robust plan for sensing liquid level during detector filling.
2.3 Trigger and Data Acquisition
2.3.1 Findings
The electronics system (Work Breakdown Schedule [WBS] 1.6 and 2.6) includes
(approximately) 20,000 APD modules, and approximately 20,000 readout front-end electronics
boards, cooling, and low- and high-voltage supplies including distribution system.
Data Acquisition (DAQ), WBS 1.7 and 2.7 includes the DAQ software, the DAQ
hardware comprising 324 data concentrators, (approximately) 20 Gigabit Ethernet switches and a
computer farm with (approximately) 260 processors. Included in this project are cables, the slow
control system, the online databases, and the integration effort.
Electronics System
The electronics system consists of (approximately) 20,000 copies of a 32-channel front-end
electronics module. Each module contains one 32-pixel APD detector and one printed-circuit board
comprising one 32-channel analog amplifier Application Specific Integrated Circuit (ASIC) with
on-chip readout multiplexer, one four-channel analog-to-digital converter chip, and one
control/readout Field Programmable Gate Array (FPGA) with high speed serial interface.
Avalanche Photo Diode: The proposed device is a modified version of an existing
Hamamatsu device. The modification is necessary mainly to accommodate two fiber ends for
each pixel. Detectors for evaluation were ordered and are expected in summer 2006. The
detectors will be bump-bonded on NOνA-supplied, printed-circuit boards by Hamamatsu.
Subsequently, the remaining board components including cables are assembled. There are some
concerns about the proximity of some bump-bonds to the detectors with an approximate 500V
potential difference between them. This could be a leakage current path that may need to be
addressed. Prototype electronics for evaluation should be available in summer 2006 well before
the required CD-2. The module/detector integration and the fiber/APD alignment needs more
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