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Register a new userModeling sidelobe response for ground-based mm-wavelength telescopes with the geometrical theory of diffraction
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Added by
Alexandre Erwin Adler
Publication date
2020
fields
Physics
and research's language is
English
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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 refractors forebaffle and the sidelobes caused by interaction with the ground screen.
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