Small Size Telescopes
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