Small Size Telescopes

SST Telescope.png

The small-size telescopes (SSTs) will cover the high end of the CTA energy range, between a few TeV and 300 TeV. About 70 SSTs are needed in order to meet CTA’s sensitivity requirements. Three different SST implementations are being prototyped and tested: one single-mirror design (SST-1M) and two dual-mirror designs (SST-2M ASTRI and SST-2M GCT). The current expectation is that the array will include 20 SST-1M telescopes, 35 ASTRI SST-2M telescopes and a similar number of SST-2M GCT telescopes. The SSTs will be built by international collaborations with contributions from institutes and universities in Poland and Switzerland (SST-1M); in Italy (ASTRI); and in Australia, France, Germany, Japan, the Netherlands, the United Kingdom and the United States (GCT).

The dual-mirror designs allow excellent imaging across a wide field of view with a short focal length. The resulting small plate scale allows the use of silicon photomultipliers (SiPMs), assembled in very compact cameras. The SST-1M also uses silicon sensors, in the form of individual hexagonal pixels equipped with light concentrators (Winston cones).

Image: An illustrative schematic of the GCT telescope with the main product assemblies.

Preparatory Phase work packages specifically related to the small telescopes are:

Small-Sized Telescope System Engineering and Integration

Design and Prototyping of the Small Telescope Structure & Optics

Design & Prototyping of the Small Telescope Camera