DocumentCode :
1517923
Title :
A High-Speed One-Dimensional Detector for Time-Resolved Small-Angle X-Ray Scattering: Design and Characterization
Author :
De Lurgio, P.M. ; Drake, G.R. ; Kreps, A.S. ; Jennings, G. ; Weizeorick, J.T. ; Molitsky, M.J. ; Naday, I. ; Hessler, J.P.
Author_Institution :
High Ener. Phys. Div., Argonne Nat. Lab., Argonne, IL, USA
Volume :
57
Issue :
3
fYear :
2010
fDate :
6/1/2010 12:00:00 AM
Firstpage :
1706
Lastpage :
1715
Abstract :
A high-speed one-dimensional detector for time-resolved small-angle x-ray scattering has been designed and built for experiments at the Advanced Photon Source of Argonne National Laboratory. This detector is made from a 500-μm thick by 150-mm diameter ultra-high-purity n-type silicon wafer. The electrodes, which are a series of concentric rings that are deposited in the wafer, integrate the scattered x-rays over the azimuthal angle and, thereby, produce a one-dimensional detector. This design yields 128 rings, which allows parallel processing of the signal from each ring. The readout electronics consist of transimpedance front-end amplifiers, one for each ring, followed by active pulse-shaping filters. The amplifier signals are digitized using 12-bit analog-to-digital converters, one per ring, which operate at 20 MHz. The frame rate of the system is 271 kHz. Up to 220 - 1 scattering profiles may be stored on a random access memory chip and transferred to a data file at a rate of 16 × 103 profiles/sec. For X-ray energies between 3.5 and 13.2 keV the efficiency exceeds 80%. The resolving time of the electronics is 300 ns, which is sufficient to isolate electronically a single pulse of scattered x-rays when the synchrotron is operated in a hybrid or asymmetric fill pattern. Therefore, laser-pump/x-ray-probe experiments can be performed without a mechanical shutter. Examples of time-resolved speckle and the kinetics of the formation of sodium chloride particles are presented. This detector is capable of acquiring small-angle x-ray scattering profiles over multiple time scales, which are needed to characterize many chemical, physical, and biological processes. In addition, this detector may be tested and calibrated before experimental runs, without access to an intense beam of x-rays, with alpha particles from a radioactive source such as 241Am.
Keywords :
X-ray detection; X-ray scattering; amplifiers; silicon radiation detectors; Advanced Photon Source; Argonne National Laboratory; Si; analog-to-digital converter; electrode; frequency 20 MHz; high speed 1D detector; random access memory chip; synchrotron; time resolved small angle X-ray scattering; transimpedance front end amplifier; ultrahigh purity n-type silicon wafer; Azimuthal angle; Electrodes; Laboratories; Particle scattering; Pulse amplifiers; Silicon; X-ray detection; X-ray detectors; X-ray lasers; X-ray scattering; Front-end electronics; silicon-strip detector; small-angle x-ray scattering; time-resolved small-angle x-ray scattering; x-ray detector;
fLanguage :
English
Journal_Title :
Nuclear Science, IEEE Transactions on
Publisher :
ieee
ISSN :
0018-9499
Type :
jour
DOI :
10.1109/TNS.2010.2045233
Filename :
5485153
Link To Document :
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