A novel double-rim forebaffle design for centimeter to sub-millimeter astrophysical observations

Jacques Delabrouille; Oliver Jeong; Michel Piat; Alexander Steier

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arXiv · 2511.16970

A novel double-rim forebaffle design for centimeter to sub-millimeter astrophysical observations

Jacques Delabrouille·Oliver Jeong·Michel Piat·Alexander Steier

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Abstract

Stray radiation of various origin is a major source of degradation of centimeter to sub-millimeter astronomical observations. This is particularly problematic for the detection of signals such as faint cosmic microwave background polarization B modes, or for mapping large-scale extragalactic or Galactic diffuse emission. In this paper, we propose a double-rim forebaffle design to reduce the impact of such stray radiation contamination. Using qualitative arguments and numerical simulations, we show that such a design has the potential to substantially improve the quality of future observations.

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Jacques Delabrouille, Oliver Jeong, Michel Piat, Alexander Steier. 2025-11-21. A novel double-rim forebaffle design for centimeter to sub-millimeter astrophysical observations. https://arxiv.org/abs/2511.16970

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