The Hybrid MPGD-based photon detectors of COMPASS RICH-1

J. Agarwala; M. Alexeev; C. D. R. Azevedo; F. Bradamante; A. Bressan; M. Buechele; C. Chatterjee; M. Chiosso; A. Cicuttin; P. Ciliberti; M. L. Crespo; S. Dalla Torre; S. Dasgupta; O. Denisov; M. Finger; M. Finger Jr.; H. Fischer; M. Gregori; G. Hamar; F. Herrmann; S. Levorato; A. Martin; G. Menon; D. Panzieri; G. Sbrizzai; S. Schopferer; M. Slunecka; M. Sulc; F. Tessarotto; J. F. C. A. Veloso; Y. Zhao

arXiv · 1812.06971

The Hybrid MPGD-based photon detectors of COMPASS RICH-1

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Abstract

Novel gaseous detectors of single photons for RICH applications have been developed and installed on COMPASS RICH-1 in 2016. They have a hybrid architecture consisting of two staggered THGEM layers (one equipped with a CsI photoconverting layer) and a bulk Micromegas; they cover a total area of 1.4 squared meters and operate stably and efficiently. They provide a single photon angular resolution of ~ 1.8 mrad and about 10 detected photons per ring at saturation. The main aspects of their construction and commissioning, their characterization and performance figures are presented.

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J. Agarwala, M. Alexeev, C. D. R. Azevedo, F. Bradamante, A. Bressan, M. Buechele, C. Chatterjee, M. Chiosso, A. Cicuttin, P. Ciliberti, M. L. Crespo, S. Dalla Torre, S. Dasgupta, O. Denisov, M. Finger, M. Finger Jr., H. Fischer, M. Gregori, G. Hamar, F. Herrmann, S. Levorato, A. Martin, G. Menon, D. Panzieri, G. Sbrizzai, S. Schopferer, M. Slunecka, M. Sulc, F. Tessarotto, J. F. C. A. Veloso, Y. Zhao. 2018-12-17. The Hybrid MPGD-based photon detectors of COMPASS RICH-1. https://arxiv.org/abs/1812.06971

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