Detailed calibration of the PI-LCX：1300 high performance single photon counting hard x-ray CCD camera

X-ray charge-coupled-device（CCD） camera working in single photon counting mode is a type of x-ray spectrometer with high-sensitivity and superior signal-to-noise performance. In this study, two single photon counting CCD cameras with the same mode（model： PI-LCX： 1300） are calibrated with quasi-monochromatic x-rays from radioactive sources and a conventional x-ray tube. The details of the CCD response to x-rays are analyzed by using a computer program of multi-pixel analyzing and event-distinguishing capability. The detection efficiency, energy resolution, fraction of multi-pixel events each as a function of x-ray energy, and consistence of two CCD cameras are obtained. The calibrated detection efficiency is consistent with the detection efficiency from Monte Carlo calculations with XOP program. When the multi-pixel event analysis is applied, the CCDs may be used to measure x-rays up to 60 ke V with good energy resolution（E /？E ≈ 100 at60 ke V）. The difference in detection efficiency between two CCD cameras is small（5.6% at 5.89 ke V）, but the difference in fraction of the single pixel event between them is much larger（25% at 8.04 ke V）. The obtained small relative error of detection efficiency（2.4% at 5.89 ke V） makes the high accurate measurement of x-ray yield possible in the laser plasma interaction studies. Based on the discrete calibration results, the calculated detection efficiency with XOP can be used for the whole range of 5 ke V–30 ke V.

A new method to suppress high-order harmonics for a synchrotron radiation soft X-ray beamline

A feasible and convenient method is proposed to suppress higher-harmonics for a varied-line-spacing plane grating monochromator in the soft X-ray region. Related calculations and experiments demonstrate that decreasing the included angle slightly by changing the parameter of the exit arm length can significantly improve light purity. This method is suitable and has been used for experiments of detector calibration in beamline 4B7B at the Beijing Synchrotron Radiation Facility （BSRF）.

A soft X-ray cryogenic radiometer built on BSRF

Introduction In the field of the high injection rate X-ray meterage,currently there are no national standards in China,which are urgently needed in areas such as inertial confinement fusion diagnosis and aerospace observation.Globally,many metrology laboratories have developed their own meterage standards based on Cryogenic radiometers.And one soft X-ray cryogenic radiometer has been installed at 4B7B experiment station on Beijing Synchrotron Radiation Facility to measure the X-ray power from 50 nW to 1μW.Purpose The purpose is to verify the accuracy of the X-ray power measurement and the performance of the cryogenic radiometer.Experimental The spectral responsivity of a Si photodiode detector calibrated in the Physikalisch-Technische Bundesanstalt of Germany is calibrated at 750eV again with the cryogenic radiometer based on synchrotron light source.Results Some important performance parameters(e.g.,time constant,responsivity,and nonequivalence error)of the cryogenic radiometer were measured and were in agreement with the design indexes.Calibration results show that total relative uncertainties of X-ray power measurement were below 1%(k=1),and that good consistency was received compared with the calibrations done by the PTB.Conclusion The cryogenic radiometer built at 4B7B is reliable and accurate for soft X-ray power measurement.And the performance of the cryogenic radiometer is also very good.