Modeling sidelobe response for ground-based mm-wavelength telescopes with the geometrical theory of diffraction [IMA]

http://arxiv.org/abs/2012.07613


Accurate optical modeling is important for the design and characterisation of current and next-generation experiments studying the Cosmic Microwave Background (CMB). Geometrical Optics (GO) cannot model diffractive effects. In this work, we discuss two methods that incorporate diffraction, Physical Optics (PO) and the Geometrical Theory of Diffraction (GTD). We simulate the optical response of a ground-based two-lens refractor design shielded by a ground screen with time-reversed simulations. In particular, we use GTD to determine the interplay between the design of the refractor’s forebaffle and the sidelobes caused by interaction with the ground screen.

Read this paper on arXiv…

A. Adler and J. Gudmundsson
Tue, 15 Dec 20
55/136

Comments: 12 pages, 10 figures, Part of SPIE Proceedings Volume 11453, Millimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy X