The RAPID2 interpolating system

A second generation of the RAPID readout electronics has been designed, built and commissioned at Daresbury Laboratory. One of the first applications is for powder diffraction on dynamic systems on the new Multi-Pole Wiggler 6.2 beam-line at the SRS. The ADC per channel system is designed to interpolate to give typically 32 pixels per channel. The Wide-Angle X-ray Scatter detector uses 128 channels of electronics to provide 4096 pixels. The target spatial resolution has a FWHM of 4 pixels, i.e. 1024 FWHM across the detector. This corresponds to approximately 400 μm FWHM over a 384 mm long (60°) curved detector. This spatial resolution requirement is more stringent than the previous generation RAPID1 system. A description of RAPID2 detailing changes to the detector design and optimisation of the lookup RAM based interpolation algorithms to meet the resolution target will be given. Initial beam-line test results will be discussed.