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Sensitivity of a Ground-Based Infrared Interferometer for Aperture Synthesis Imaging

Tadashi Nakajima
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Abstract

Sensitivity limits of ground-based infrared interferometers using aperture synthesis are presented. The motivation of this analysis is to compare an interferometer composed of multiple large telescopes and a single giant telescope with adaptive optics. In deriving these limits, perfect wavefront correction by adaptive optics and perfect cophasing by fringe tracking are assumed. We consider the case in which n beams are pairwise combined at n(n-1)/2 detectors and the case in which all the n beams are combined at a single detector. As a case study, we compare the point-source sensitivities of interferometers composed of nine 10-m diameter telescopes and a 30-m diameter single telescope with adaptive optics between 1 and 10 microns.

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Tadashi Nakajima. 2001-07-16. Sensitivity of a Ground-Based Infrared Interferometer for Aperture Synthesis Imaging. https://doi.org/10.1086/323285

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