Si-APD array detectors with 2ns pulse-pair resolving time and sub-ns resolution for synchrotron X-ray measurements

Abstract

Silicon avalanche photodiode (Si-APD) array detectors have been developed for synchrotron X-ray experiments. A Si-APD 8×2 array detector (pixel size—200×200 μm 2 ) provided ultra-fast pulses for Mössbauer micro-spectroscopy on 57 Fe using synchrotron X-rays. The pulse width was 0.9 ns (FWHM) at the amplifiers’ outputs. A 64-channnel linear-array detector was also prepared for time-resolved measurements using pulsed X-rays. A pixel size of 100×200 μm 2 and a sensitive region of 64 pixels, 9.6 mm long, were designed in the linear array. The time resolution Δ T (FWHM) is expected to be 100 ps from the device design. An ASIC with an ultra-fast front-end circuit will be used for time-resolved X-ray diffraction measurements with a 2 ns pulse-pair resolving time.