An Algorithm of an X-ray Hit Allocation to a Single Pixel in a Cluster and Its Test-Circuit Implementation

Journal Article · 28 June 2017 · IEEE Transactions on Circuits and Systems I: Regular Papers

DOI: https://doi.org/10.1109/TCSI.2017.2713767 · OSTI ID:1438317

Deptuch, Grzegorz W.  ^[1]; Fahim, Farah ^[1]; Grybos, Pawel ^[2]; Hoff, Jim ^[1]; Holm, Scott ^[1]; Maj, Piotr ^[2]; Siddons, David Peter ^[3]; Kmon, Piotr ^[2]; Trimpl, Marcel ^[1]; Zimmerman, Tom ^[1]

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1. Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
2. AGH Univ. of Science and Technology, Krakow (Poland)
3. Brookhaven National Lab. (BNL), Upton, NY (United States)

An on-chip implementable algorithm for allocation of an X-ray photon imprint, called a hit, to a single pixel in the presence of charge sharing in a highly segmented pixel detector is described. Its proof-of-principle implementation is also given supported by the results of tests using a highly collimated X-ray photon beam from a synchrotron source. The algorithm handles asynchronous arrivals of X-ray photons. Activation of groups of pixels, comparisons of peak amplitudes of pulses within an active neighborhood and finally latching of the results of these comparisons constitute the three procedural steps of the algorithm. A grouping of pixels to one virtual pixel, that recovers composite signals and event driven strobes, to control comparisons of fractional signals between neighboring pixels are the actuators of the algorithm. The circuitry necessary to implement the algorithm requires an extensive inter-pixel connection grid of analog and digital signals, that are exchanged between pixels. A test-circuit implementation of the algorithm was achieved with a small array of 32 × 32 pixels and the device was exposed to an 8 keV highly collimated to a diameter of 3-μm X-ray beam. Furthermore, the results of these tests are given in this paper assessing physical implementation of the algorithm.

• Research Organization: Brookhaven National Laboratory (BNL), Upton, NY (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: SC0012704
• OSTI ID: 1438317
• Report Number(s): BNL-205675-2018-JAAM
• Journal Information: IEEE Transactions on Circuits and Systems I: Regular Papers, Vol. 65, Issue 1; ISSN 1549-8328
• Publisher: IEEECopyright Statement
• Country of Publication: United States
• Language: English