Novel silicon photomultipliers suitable for dual-mirror small-sized telescopes of the Cherenkov telescope array
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| Author(s): |
Total Authors: 4
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| Affiliation: | [1] Osserv Astrofis Catania, INAF, Via S Sofia 78, I-95123 Catania - Italy
[2] INAF Osservatorio Astron Brera, Via Emilio Bianchi 46, I-23807 Merate, LC - Italy
Total Affiliations: 2
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| Document type: | Review article |
| Source: | NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SP; v. 908, p. 117-127, NOV 11 2018. |
| Web of Science Citations: | 1 |
| Abstract | |
Many of the characteristics of Silicon Photomultipliers (SiPMs), such as high Photon Detection Efficiency (PDE), are well matched to the requirements of the cameras of the Small-Sized Telescopes (SSTs) proposed for the Cherenkov Telescope Array. In fact, compared to a single mirror, the double mirror Schwarzschild-Couder configuration provides a much better Point Spread Function over a large field of view. It allows better correction of aberrations at large off-axis angles and facilitates the construction of compact telescopes. Moreover, the small plate scale of the dual-mirror SSTs allows the use of SiPM detectors despite their small pixel sizes. These sensors have two further advantages compared to the Photo Multipliers Tubes: the low cost and the possibility to observe in very high Night Sky Background (NSB) light level without any damage. However, one area in which SiPM performance has required improvement is Optical Cross-Talk (OCT), where multiple avalanches are induced by a single impinging photon. OCT, coupled with the typical NSB rate of 25 MCnts/s per pixel during Cherenkov observations, can place severe constraints on the triggering capability of the cameras. This paper describes the performance of novel Low Voltage Reverse (LVR) 2nd and 3rd generation Multi-Pixel Photon Counters manufactured by Hamamatsu Photonics. These are designed to have both enhanced PDE and reduced OCT. Two 7 x 7 mm(2) S14520 LVR2 MPPCs with 75 mu m micro-cells are tested and compared with detectors of the same pixel size with 50 mu m micro-cells. A comparative analysis of a 3 x 3 mm(2) S14520 LVR2 device and an S14520 LVR3 device is also carried out, demonstrating that the LVR3 gives better photon detection in the 240 - 380 nm wave-length range. Finally, the effect of an infrared filter on the OCT is analysed. (AU) | |
| FAPESP's process: | 13/10559-5 - Investigation of high energy and plasma astrophysics phenomena: theory, numerical simulations, observations, and instrument development for the Cherenkov Telescope Array (CTA) |
| Grantee: | Elisabete Maria de Gouveia Dal Pino |
| Support type: | Research Projects - Thematic Grants |