Construction of a Schwarzschild-Couder telescope as a candidate for the Cherenkov Telescope Array: status of the optical system

TL;DR

This paper discusses the design and development status of the optical system for a prototype Schwarzschild-Couder telescope, a candidate for the Cherenkov Telescope Array, focusing on its innovative optical design and manufacturing challenges.

Contribution

It presents the detailed optical design, manufacturing solutions, and integration plans for the Schwarzschild-Couder telescope's optical system, advancing the development of gamma-ray observatories.

Findings

Design of a novel aplanatic optical system with segmented mirrors

Achieved point spread function better than 4 arcmin within 6.4-degree FOV

Developed manufacturing and alignment solutions for aspheric mirror panels

Abstract

We present the design and the status of procurement of the optical system of the prototype Schwarzschild-Couder telescope (pSCT), for which construction is scheduled to begin in fall at the Fred Lawrence Whipple Observatory in southern Arizona, USA. The Schwarzschild-Couder telescope is a candidate for the medium-sized telescopes of the Cherenkov Telescope Array, which utilizes imaging atmospheric Cherenkov techniques to observe gamma rays in the energy range of 60Gev-60TeV. The pSCT novel aplanatic optical system is made of two segmented aspheric mirrors. The primary mirror has 48 mirror panels with an aperture of 9.6 m, while the secondary, made of 24 panels, has an diameter of 5.4 m. The resulting point spread function (PSF) is required to be better than 4 arcmin within a field of view of 6.4 degrees (80% of the field of view), which corresponds to a physical size of 6.4 mm on the focal plane. This goal represents a challenge for the inexpensive fabrication of aspheric mirror panels and for the precise alignment of the optical system as well as for the rigidity of the optical support structure. In this submission we introduce the design of the Schwarzschild-Couder optical system and describe the solutions adopted for the manufacturing of the mirror panels and their integration with the optical support structure.