The Use of single-crystal CVD diamond X-ray beam diagnostics for synchrotron beamline commissioning and operation at diamond light source Ltd

We report on the use of single-crystal chemical vapour deposition (scCVD) diamond X-ray beam diagnostics at Diamond Light Source Ltd (DLS) for beamline commissioning and day-to-day beamline operation. It is demonstrated that such detectors can offer synchrotron beamlines a measurement of the X-ray beam position with resolutions of a few 10nm at kHz bandwidths. It is straightforward to extract extremely valuable spectral information of both beam motion and intensity, aiding beamlines in determining the source of vibrations or other beam instabilities. In this paper we discuss the motivation behind the use of single-crystal diamond detectors for monitoring monochromatic X-ray beams, and advantages over other diagnostic techniques are discussed. In order to absolutely quantify the performance of the diamond detectors in use at DLS an experiment has been conducted with three diamond X-ray beam position monitors installed on a beamline, longitudinally separated along the beam path by ~10 millimeters and intercepting the same incident X-ray beam. Measurements from each of the three diamond detectors were synchronously acquired at kHz bandwidths. Other, independent measurements were employed to corroborate the measurements obtained from the three X-ray beam position monitors. The uncorrelated position measurement noise recorded by the synchronous measurements and is shown to be less than 1% of beam size at this bandwidth. Longer integration times resulted in correspondingly less measurement noise.