Prototype 9.7 m Schwarzschild-Couder telescope for the Cherenkov Telescope Array: status of the optical system

D. Nieto; T. B. Humensky; P. Kaaret; D. Kieda; M. Limon; A. Petrashyk; D. Ribeiro; J. Rousselle; B. Stevenson; V. Vassiliev; P. Wilcox

arXiv · 1709.06324

Prototype 9.7 m Schwarzschild-Couder telescope for the Cherenkov Telescope Array: status of the optical system

D. Nieto·T. B. Humensky·P. Kaaret·D. Kieda·M. Limon·A. Petrashyk·D. Ribeiro·J. Rousselle·B. Stevenson·V. Vassiliev·P. Wilcox

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Abstract

The Cherenkov Telescope Array (CTA) is an international project for a next-generation ground-based gamma ray observatory, aiming to improve on the sensitivity of current-generation experiments by an order of magnitude and provide energy coverage from 30 GeV to more than 300 TeV. The 9.7m Schwarzschild-Couder (SC) candidate medium-size telescope for CTA exploits a novel aplanatic two-mirror optical design that provides a large field of view of 8 degrees and substantially improves the off-axis performance giving better angular resolution across all of the field of view with respect to single-mirror telescopes. The realization of the SC optical design implies the challenging production of large aspherical mirrors accompanied by a submillimeter-precision custom alignment system. In this contribution we report on the status of the implementation of the optical system on a prototype 9.7 m SC telescope located at the Fred Lawrence Whipple Observatory in southern Arizona.

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D. Nieto, T. B. Humensky, P. Kaaret, D. Kieda, M. Limon, A. Petrashyk, D. Ribeiro, J. Rousselle, B. Stevenson, V. Vassiliev, P. Wilcox. 2017-09-19. Prototype 9.7 m Schwarzschild-Couder telescope for the Cherenkov Telescope Array: status of the optical system. https://arxiv.org/abs/1709.06324

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