Third Level Trigger for the Fluorescence Telescopes of the Pierre Auger Observatory

A. Schmidt; T. Asch; H. Gemmeke; M. Kleifges; H. -J. Mathes; A. Menshikov; F. Schüssler; D. Tcherniakhovski

doi:10.1016/j.nima.2009.01.002

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arXiv · 0807.4421

Third Level Trigger for the Fluorescence Telescopes of the Pierre Auger Observatory

A. Schmidt·T. Asch·H. Gemmeke·M. Kleifges·H. -J. Mathes·A. Menshikov·F. Schüssler·D. Tcherniakhovski

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Abstract

The trigger system for the Auger fluorescence telescopes is implemented in hard- and software for an efficient selection of fluorescence light tracks induced by high-energy extensive air showers. The algorithm of the third stage uses the multiplicity signal of the hardware for fast rejection of lightning events with above 99% efficiency. In a second step direct muon hits in the camera and random triggers are rejected by analyzing the space-time correlation of the pixels. The trigger algorithm was tested with measured and simulated showers and implemented in the electronics of the fluorescence telescopes. A comparison to a prototype trigger without multiplicity shows the superiority of this approach, e.g. the false rejection rate is a factor 10 lower.

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A. Schmidt, T. Asch, H. Gemmeke, M. Kleifges, H. -J. Mathes, A. Menshikov, F. Schüssler, D. Tcherniakhovski. 2008-08-01. Third Level Trigger for the Fluorescence Telescopes of the Pierre Auger Observatory. https://doi.org/10.1016/j.nima.2009.01.002

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