Schwarzschild-Couder two-mirror telescope for ground-based gamma-ray astronomy

V. V. Vassiliev; S. J. Fegan

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arXiv · 0708.2741

Schwarzschild-Couder two-mirror telescope for ground-based gamma-ray astronomy

V. V. Vassiliev·S. J. Fegan

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Abstract

Schwarzschild-type aplanatic telescopes with two aspheric mirrors, configured to correct spherical and coma aberrations, are considered for application in gamma-ray astronomy utilizing the ground-based atmospheric Cherenkov technique. We use analytical descriptions for the figures of primary and secondary mirrors and, by means of numerical ray-tracing, we find telescope configurations which minimize astigmatism and maximize effective light collecting area. It is shown that unlike the traditional prime-focus Davies-Cotton design, such telescopes provide a solution for wide field of view gamma-ray observations. The designs are isochronous, can be optimized to have no vignetting across the field, and allow for significant reduction of the plate scale, making them compatible with finely-pixilated cameras, which can be constructed from modern, cost-effective image sensors such as multi-anode PMTs, SiPMs, or image intensifiers.

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V. V. Vassiliev, S. J. Fegan. 2007-08-21. Schwarzschild-Couder two-mirror telescope for ground-based gamma-ray astronomy. https://arxiv.org/abs/0708.2741

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