Improved X-ray detection and particle identification with avalanche photodiodes

Marc Diepold; Luis M. P. Fernandes; Jorge Machado; Pedro Amaro; Marwan Abdou-Ahmed; Fernando D. Amaro; Aldo Antognini; François Biraben; Tzu-Ling Chen; Daniel S. Covita; Andreas J. Dax; Beatrice Franke; Sandrine Galtier; Andrea L. Gouvea; Johannes Götzfried; Thomas Graf; Theodor W. Hänsch; Malte Hildebrandt; Paul Indelicato; Lucile Julien; Klaus Kirch; Andreas Knecht; Franz Kottmann; Julian J. Krauth; Yi-Wei Liu; Cristina M. B. Monteiro; Françoise Mulhauser; Boris Naar; Tobias Nebel; François Nez; José Paulo Santos; Joaquim M. F. dos Santos; Karsten Schuhmann; Csilla I. Szabo; David Taqqu; João F. C. A. Veloso; Andreas Voss; Birgit Weichelt; Randolf Pohl

doi:10.1063/1.4921195

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arXiv · 1505.06879

Improved X-ray detection and particle identification with avalanche photodiodes

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Abstract

Avalanche photodiodes are commonly used as detectors for low energy x-rays. In this work we report on a fitting technique used to account for different detector responses resulting from photo absorption in the various APD layers. The use of this technique results in an improvement of the energy resolution at 8.2 keV by up to a factor of 2, and corrects the timing information by up to 25 ns to account for space dependent electron drift time. In addition, this waveform analysis is used for particle identification, e.g. to distinguish between x-rays and MeV electrons in our experiment.

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Marc Diepold, Luis M. P. Fernandes, Jorge Machado, Pedro Amaro, Marwan Abdou-Ahmed, Fernando D. Amaro, Aldo Antognini, François Biraben, Tzu-Ling Chen, Daniel S. Covita, Andreas J. Dax, Beatrice Franke, Sandrine Galtier, Andrea L. Gouvea, Johannes Götzfried, Thomas Graf, Theodor W. Hänsch, Malte Hildebrandt, Paul Indelicato, Lucile Julien, Klaus Kirch, Andreas Knecht, Franz Kottmann, Julian J. Krauth, Yi-Wei Liu, Cristina M. B. Monteiro, Françoise Mulhauser, Boris Naar, Tobias Nebel, François Nez, José Paulo Santos, Joaquim M. F. dos Santos, Karsten Schuhmann, Csilla I. Szabo, David Taqqu, João F. C. A. Veloso, Andreas Voss, Birgit Weichelt, Randolf Pohl. 2015-05-26. Improved X-ray detection and particle identification with avalanche photodiodes. https://doi.org/10.1063/1.4921195

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