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arXiv · 1802.05715

An image-based array trigger for Imaging Atmospheric Cherenkov Telescope Arrays

Hugh Dickinson·Frank Krennrich·Amanda Weinstein·Jonathan Eisch·Karen Byrum·John Anderson·Gary Drake
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Abstract

It is anticipated that forthcoming, next generation, atmospheric Cherenkov telescope arrays will include a number of medium-sized telescopes that are constructed using a dual-mirror Schwarzschild-Couder configuration. These telescopes will sample a wide ($8^{\circ}$) field of view using a densely pixelated camera comprising over $10^{4}$ individual readout channels. A readout frequency congruent with the expected single-telescope trigger rates would result in substantial data rates. To ameliorate these data rates, a novel, hardware-level Distributed Intelligent Array Trigger (DIAT) is envisioned. A copy of the DIAT operates autonomously at each telescope and uses reduced resolution imaging data from a limited subset of nearby telescopes to veto events prior to camera readout {and any subsequent network transmission of camera data that is required for centralized storage or aggregation}. We present the results of Monte-Carlo simulations that evaluate the efficacy of a "Parallax width" discriminator that can be used by the DIAT to efficiently distinguish between genuine gamma-ray initiated events and unwanted background events that are initiated by hadronic cosmic rays.

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Hugh Dickinson, Frank Krennrich, Amanda Weinstein, Jonathan Eisch, Karen Byrum, John Anderson, Gary Drake. 2018-02-15. An image-based array trigger for Imaging Atmospheric Cherenkov Telescope Arrays. https://doi.org/10.1016/j.nima.2018.02.048

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