Accessing Small Inner Working Angles with a Rotating Sub-Aperture Nuller

Serabyn, Eugene; Mennesso, B.

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NASA NTRS · 20070032003

Accessing Small Inner Working Angles with a Rotating Sub-Aperture Nuller

Serabyn, Eugene·Mennesso, B.

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Abstract

A new approach to high contrast observations near bright stars with a single-aperture telescope is discussed, which is based on the idea of a rotating separated-aperture nulling interferometer. The approach can be described as a rotating sub-aperture nuller, because it nulls two or more sub-apertures within a single telescope's pupil, and uses baseline rotation to modulate the signals from off-axis sources in a manner similar to that of potential space-based nulling interferometers. The sub-aperture beams can be combined in a number of ways, including a fiber nuller and a rotational shearing interferometer. Such a rotating nulling coronagraph has two great advantages. First, it can be used on a ground-based telescope to test signal reconstruction approaches pertinent to potential space-based nulling interferometers. Moreover, it also has the potential to enable ground-based coronagraphic observations of faint off-axis companions very close to bright stars.

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Serabyn, Eugene, Mennesso, B.. 2005-10-03. Accessing Small Inner Working Angles with a Rotating Sub-Aperture Nuller. https://ntrs.nasa.gov/citations/20070032003

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