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Phase Referencing and Narrow-Angle Astrometry in Current and Future Interferometers

Benjamin F. Lane·Matthew W. Muterspaugh
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Abstract

Atmospheric turbulence is a serious problem for ground-based interferometers. It places tight limits on both sensitivity and measurement precision. Phase referencing is a method to overcome these limitations via the use of a bright reference star. The Palomar Testbed Interferometer was designed to use phase referencing and so can provide a pair of phase-stabilized starlight beams to a second (science) beam combiner. We have used this capability for several interesting studies, including very narrow angle astrometry. For close (1-arcsecond) pairs of stars we are able to achieve a differential astrometric precision in the range 20-30 micro-arcseconds.

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Benjamin F. Lane, Matthew W. Muterspaugh. 2004-07-14. Phase Referencing and Narrow-Angle Astrometry in Current and Future Interferometers. https://doi.org/10.1117/12.549440

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