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arXiv · 0811.2264

Astrometry with the Keck-Interferometer: the ASTRA project and its science

Jorg-Uwe Pott·Julien Woillez·Rachel L. Akeson·Ben Berkey·Mark M. Colavita·Andrew Cooper·Josh A. Eisner·Andrea M. Ghez·James R. Graham·Lynne Hillenbrand·Michael Hrynewych·Drew Medeiros·Rafael Millan-Gabet·John Monnier·Douglas Morrison·Tatyana Panteleeva·Eliot Quataert·Bill Randolph·Brett Smith·Kellee Summers·Kevin Tsubota·Colette Tyau·Nevin Weinberg·Ed Wetherell·Peter L. Wizinowich
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Abstract

The sensitivity and astrometry upgrade ASTRA of the Keck Interferometer is introduced. After a brief overview of the underlying interferometric principles, the technology and concepts of the upgrade are presented. The interferometric dual-field technology of ASTRA will provide the KI with the means to observe two objects simultaneously, and measure the distance between them with a precision eventually better than 100 uas. This astrometric functionality of ASTRA will add a unique observing tool to fields of astrophysical research as diverse as exo-planetary kinematics, binary astrometry, and the investigation of stars accelerated by the massive black hole in the center of the Milky Way as discussed in this contribution.

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Jorg-Uwe Pott, Julien Woillez, Rachel L. Akeson, Ben Berkey, Mark M. Colavita, Andrew Cooper, Josh A. Eisner, Andrea M. Ghez, James R. Graham, Lynne Hillenbrand, Michael Hrynewych, Drew Medeiros, Rafael Millan-Gabet, John Monnier, Douglas Morrison, Tatyana Panteleeva, Eliot Quataert, Bill Randolph, Brett Smith, Kellee Summers, Kevin Tsubota, Colette Tyau, Nevin Weinberg, Ed Wetherell, Peter L. Wizinowich. 2008-11-14. Astrometry with the Keck-Interferometer: the ASTRA project and its science. https://doi.org/10.1016/j.newar.2010.07.009

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