Characterisation of CVD diamond devices as XBPMs at SOLEIL

Abstract

Single crystal CVD diamonds have been developed for use as XBPMs on the beamlines of the French synchrotron SOLEIL. These devices have been calibrated and characterized directly on the beamline following an elaborate protocol. An example is given for an XBPM installed on PROXIMA 2. This device has shown a charge collection efficiency of 100% for only 0.2V/μm with total signal-to-noise ratio better than 105. A complete 2D scan gives the homogeneity of the scale factors over the active surface with a very low error corresponding to 0.6μm (beam off-center and maximum calibration error). The current sensitivity measurement shows a fluctuation less than 0.02% and the responsivity is calculated to measure the incident flux. And finally, the spatial resolution for these XBPMs is better than 1μm rms at 1kHz and 100 nm rms at 5 Hz.