Rad-Hard Dual-Threshold High Count Rate Silicon Pixel Array Detector

Available 2D multiwire proportional counters (MWPC) are limited by their low global countrate capability and are insufficient for imaging XCS (xray crystal spectroscopy) experiments. Solid state xray pixilated array detectors have been shown to overcome this problem. However, large area solid state 2D detectors with higher performance, increased functionality, and dualthreshold capabilities are needed for planned experiments. Because of the harsh environment inside the tokamak vacuum vessel, these detectors must also function and perform with high reliability in conditions not previously encountered by diagnostic technology. A prototype of a high performance xray pixilated array detector (PAD) will be demonstrated. Each pixel of the PAD is configured with spectroscopic amplifier features, including programmablegain lownoise preamplifier and variable bandwidth pulse shaping circuits. Enhanced xray photon counting functions are also included. Following the amplifier circuits in each pixel are two programmable pulse discrimination circuits (comparators) and two programmable, separatelygateable counters. Each counter, individually userprogrammed, allows for gating. The two counters can be enabled simultaneously or be gated for interleaved counting. Also, the counters can be configured as two separate 15bit counters or as a single 30bit counter. Another included feature is integrate whileread. The pixels can count photons at over 100 MHz rates. In Phase II, incorporating the performance and features required by the target users, a new PAD will be fabricated and demonstrated with camera electronics. Commercial applications and other benefits: The innovation has application to a range of high energy physics (HEP), nuclear physics, and other science applications. The innovation also has applicability for medical applications including digital mammography, PET, SPECT, and others. Other applications include homeland security, nuclear weapons monitoring, as well as industrial inspection.