Gamma Air Watch (GAW): the electronics and trigger concept

P. Assis; G. Agnetta; P. Brogueira; O. Catalano; G. Cusumano; N. Galli; S. Giarrusso; G. la Rosa; M. Pimenta; G. Pires; F. Russo; B. Sacco

arXiv · 0707.4462

Gamma Air Watch (GAW): the electronics and trigger concept

P. Assis·G. Agnetta·P. Brogueira·O. Catalano·G. Cusumano·N. Galli·S. Giarrusso·G. la Rosa·M. Pimenta·G. Pires·F. Russo·B. Sacco

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Abstract

GAW proposes a new approach for the detection and measurement of the Cherenkov light produced by GeV/TeV gamma rays traversing the Earth atmosphere which imposes specific requirements on the electronics design. The focal surface of the GAW telescope consists of a matrix of multi-anode photomultipliers. The large number of active channels (of the order of 10^5) makes it basically a large UV sensitive digital camera with high resolution imaging capability. The limited amount of space available, due to the large number of channels, requires a compact design with minimal distance between the elements of the focal surface. The front-end electronics uses the single photoelectron counting technique to capture the Cherenkov light. The data acquisition is based on free-running data taking method. Self-triggering capability for each telescope is assured by detecting an excess of active pixels, in a 10ns time frame, inside overlapping trigger areas covering the whole focal surface. In this paper we describe the GAW electronics, as well as the trigger concept and implementation.

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P. Assis, G. Agnetta, P. Brogueira, O. Catalano, G. Cusumano, N. Galli, S. Giarrusso, G. la Rosa, M. Pimenta, G. Pires, F. Russo, B. Sacco. 2007-07-30. Gamma Air Watch (GAW): the electronics and trigger concept. https://arxiv.org/abs/0707.4462

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