Silicon X-ray Detectors and Data Acquisition for LCLS Science Instruments
In 2009 the Linac Coherent Light Source (LCLS), a fourth generation light source producing extremely short (100 fs) and ultra bright x-ray pulses, will become operational at the Stanford Linear Accelerator Center. Several experiments are currently under development and will begin acquiring data in 2009. The experiments require large area pixel detectors with small (<100 micrometer) pixel size, 120 Hz readout, high dynamic range (up to 104 photons per pixel), low noise (<< 1 photon) and high quantum efficiency (>90 % at 8 keV). I will present the status of two detector programs initiated by the LCLS project to meet these scientific needs. The first program is a hybrid pixel array detector that is being developed at Cornell University. This detector consists of a Si-diode sensor, bump bonded to a readout ASIC with in-pixel digitization. The second program, currently underway at Brookhaven National Laboratory, will develop two detector systems based on an X-Ray Active Matrix Pixel Sensor concept. Additionally, I will briefly discuss the various data acquisition and data storage challenges and the current architectures that are needed for the LCLS science instruments. The LCLS experiments will generate multi-mega pixel two dimensional images with up to 14 bit resolution. This requires a data acquisition system with at least 5 Gbit/s data streaming with the capability to scale for future experiments with larger detectors.
