X-ray analog pixel array detector for single synchrotron bunch time-resolved imaging

Abstract

Dynamic X-ray studies can reach temporal resolutions limited by only the X-ray pulse duration if the detector is fast enough to segregate synchrotron pulses. An analog integrating pixel array detector with in-pixel storage and temporal resolution of around 150 ns, sufficient to isolate pulses, is presented. Analog integration minimizes count-rate limitations and in-pixel storage captures successive pulses. Fundamental tests of noise and linearity as well as high-speed laser measurements are shown. The detector resolved individual bunch trains at the Cornell High Energy Synchrotron Source at levels of up to 3.7 Â 10 3 X-rays per pixel per train. When applied to turn-by-turn X-ray beam characterization, single-shot intensity measurements were made with a repeatability of 0.4% and horizontal oscillations of the positron cloud were detected.

High-speed x-ray imaging with the Keck pixel array detector (Keck PAD) for time-resolved experiments at synchrotron sources

“…Beyond gain control, the feedback capacitors can be individually selected and cycled through without reset while acquiring data to allow for repeated sampling of cyclical processes before readout. In some situations, this improves the fidelity of the signal collected and provides an efficient avenue to collect charge without the relatively lengthy process of readout [10].…”

“…The first is a fast front-end amplifier that is capable of slewing charge on capacitors but maintains a relatively low quiescent current when charge is not being collected. This is achieved using a class AB amplifier design [10]. The second is four selectable feedback capacitors on the front-end that allow for the chargeto-voltage gain of the transimpedance integrating AB amplifier to be adjusted to levels appropriate for the data being collected.…”

“…The Keck PAD versions presented in this paper use full-scale detector chips with 128×128 pixels, and represents an enlarged version of previous 16×16 pixel prototypes [5,6]. Similar in-pixel data storage techniques have also been incorporated into the Adaptive Gain Integrating Pixel Array Detector (AGIPD) [7].…”

Pulse-resolved multi-photon X-ray detection at 31 MHz based on a quadrant avalanche photodiode

“…the AGIPD (Henrich et al, 2011), the CSPAD (Herrmann et al, 2013), the Analog integrating pixel array detector (Koerner & Gruner, 2011) or the single-photon-counting XNAP (Fajardo et al, 2013)], the digitalization of an unlimited number of subsequent X-ray pulses at a temporal spacing of 30 ns, the easy integration into any beamline set-up at synchrotron or FEL sources (suitable timing signals provided), the high flexibility of the quadrant approach and the comparatively low production cost can make the QAPD a useful device. Future improvements include the implementation of fully differential analog signalling as well as extensive testing of alternative detector front-ends (including CVD diamond, GaAs and CdTe-based materials).…”

High-speed X-ray imaging pixel array detector for synchrotron bunch isolation

“…The detector described in this article is a second-generation device that overcomes some of the limitations. The design of the pixel was tested in a 16 Â 16 pixel format (Koerner, 2010;Koerner et al, 2009;Koerner & Gruner, 2011). The detector described in this paper is a full-scale application-specific integrated circuit (ASIC) suitable for X-ray imaging experiments at synchrotrons.…”