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Narrow-Angle and Wide-Angle Astrometry via Long Baseline Optical/Infrared Interferometers

Published online by Cambridge University Press:  07 August 2017

Xiaopei Pan ,
Shri Kulkarni ,
Michael Shao  and
M. Mark Colavita
Xiaopei Pan
Affiliation:
California Institute of Technology, Pasadena, CA 91125
Shri Kulkarni
Affiliation:
California Institute of Technology, Pasadena, CA 91125
Michael Shao
Affiliation:
Jet Propulsion Laboratory, Pasadena, CA 91109
M. Mark Colavita
Affiliation:
Jet Propulsion Laboratory, Pasadena, CA 91109

Abstract

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Long baseline optical/infrared interferometers, such as the Mark III Stellar Interferometer1 on Mt. Wilson and the ASEPS-0 Testbed Interferometer2 on Palomar Mountain, California, have good capabilities for narrow-angle and wide-angle astrometry with very high precision. Using the Mark III Interferometer many spectroscopic binaries became “visual” for the first time. The measurement accuracy of angular separation is 0.2 mas, the smallest separation measured between two components is 2 mas, the maximum magnitude difference is 4 mag, and the smallest semimajor axis is 4 mas. Such high angular resolution and dynamic range have been used to determine stellar masses with precision of 2% and differential stellar luminosities to better than 0.05 mag for separations of less than 0.″2. For some binary stars, not only have the systems been resolved, but also the diameter of the primary component has been determined, yielding direct measurements of stellar effective temperature with high accuracy. For parallax determination, the precision is 1 mas or better and is unaffected by interstellar extinction. For wide-angle astrometry with the Mark III interferometer, the observation results yielded average formal 1σ errors for FK5 stars of about 10 mas. Presently a new infrared interferometer, the ASEPS-0 Testbed Interferometer on Palomar Mountain is under construction, and is being optimized to perform high accuracy narrow-angle astrometry using long baseline observations at 2.2 μm, with phase referencing for increased sensitivity. The goal is to demonstrate differential astrometric accuracies of 0.06–0.1 mas3 in order to allow for detection of extra-solar planets in the near future.

Keywords

astrometryoptical/IR interferometer
Type
1. Current Advances in Astrometry
Information
Symposium - International Astronomical Union , Volume 166: Astronomical and Astrophysical Objectives of Sub-Milliarcsecond Optical Astrometry , 1995 , pp. 13 - 18
Copyright
Copyright © Kluwer 1995 

References

1. Shao, M. et al. 1988, A & A, 193, 357 Google Scholar
2. Colavita, M. M. et al. 1994, Proc. SPIE, 2200, 89 Google Scholar
3. Colavita, M. M. 1994, A & A, 283, 1027 Google Scholar
4. Pan, X.P. et al. 1992, ApJ, 384, 624 Google Scholar
5. Pan, X.P. et al. 1990, Proc. SPIE, 1237, 301 Google Scholar
6. Pan, X.P. et al. 1993, IAU Coll. 135, 502 Google Scholar
7. Pan, X.P. et al. 1994, Pro. SPIE, 2200, 360 CrossRefGoogle Scholar
8. Armstrong, J.T. et al. 1992, AJ, 104, 2217 Google Scholar
9. Pan, X.P. et al. 1993, ApJ, 413, L129 CrossRefGoogle Scholar
10. Shao, M. et al. 1990, AJ, 100, 1701 Google Scholar