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Quasar Astrophysics with the Space Interferometry Mission

Published online by Cambridge University Press:  05 March 2013

S. C. Unwin
Affiliation:
Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA; Stephen.C.Unwin@jpl.nasa.gov
A. E. Wehrle
Affiliation:
Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA; Ann.E.Wehrle@jpl.nasa.gov
D. L. Jones
Affiliation:
Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA; Dayton.L.Jones@jpl.nasa.gov
D. L. Meier
Affiliation:
Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA; David.L.Meier@jpl.nasa.gov
B. G. Piner
Affiliation:
Department of Physics and Astronomy, Whittier College, 13406 E. Philadelphia Street, Whittier, CA 90608, USA; gpiner@whittier.edu
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Abstract

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Precision optical astrometry of quasars and active galaxies can provide important insight into the spatial distribution and variability of emission in compact nuclei. SIM — the Space Interferometry Mission — will be the first optical interferometer capable of precision astrometry on quasars. Although it is not expected to resolve the emission, it will be very sensitive to astrometric shifts, for objects as faint as R magnitude 20. In its wide-angle mode, SIM will yield 4 microarcsecond absolute positions, and proper motions to about 2 microarcsecond/yr. A variety of AGN phenomena are expected to be visible to SIM on these scales, including time and spectral dependence in position offsets between accretion disk and jet emission. SIM should be able to answer the following questions. Does the most compact optical emission from an AGN come from an accretion disk or from a relativistic jet? Do the relative positions of the radio core and optical photocentre of quasars used for the reference frame tie change on the timescales of their photometric variability? Do the cores of galaxies harbour binary supermassive black holes remaining from galaxy mergers? In this paper we briefly describe the operation of SIM and the quasar measurements it will make. We estimate the size of the astrometric signatures which may be expected, and we discuss prospects for using astrometry as a fundamental tool for understanding quasar nuclei.

Type
Research Article
Copyright
Copyright © Astronomical Society of Australia 2002

References

Band, D. L., & Malkan, M. A. 1989, ApJ, 345, 122 CrossRefGoogle Scholar
Biretta, J. A., Stern, C. P., & Harris, D. E. 1991, AJ, 101, 1632 CrossRefGoogle Scholar
Blandford, R. D. 1999, in Astrophysical Disks, ASP Conf. Ser. 160, ed. J. A. Sellwood, & J. J. Goodman (San Francisco: ASP) 265 Google Scholar
Blandford, R. D., & Königl, A. 1979, ApJ, 232, 34 CrossRefGoogle Scholar
Böker, T., & Allen, R. J. 1999, ApJS, 125, 123 CrossRefGoogle Scholar
Fey, A. L., et al. 2001, AJ, 121, 1741 CrossRefGoogle Scholar
Gaskell, C. M. 1996, ApJ, 464, L107 CrossRefGoogle Scholar
Gould, A., & Rix, H. 2000, ApJ, 532, L29 CrossRefGoogle Scholar
Hutter, D. J., & Mufson, S. L. 1986, ApJ, 301, 50 CrossRefGoogle Scholar
Kidger, M. R. 2000, AJ, 119, 2053 CrossRefGoogle Scholar
Königl, A. 1981, ApJ, 243, 700 CrossRefGoogle Scholar
Lehto, H. J., & Valtonen, M. J. 1996, ApJ, 460, 207 CrossRefGoogle Scholar
Ma, C., et al. 1998, AJ, 116, 516 CrossRefGoogle Scholar
Marcaide, J. M., & Shapiro, I. I. 1984, ApJ, 276, 56 CrossRefGoogle Scholar
Meier, D. L. 1999, ApJ, 522, 753 CrossRefGoogle Scholar
Milosavljevic, M., & Merritt, D. 2000, BAAS, 196, 2916 Google Scholar
Osterbrock, D. E., & Matthews, W. G. 1986, ARAA, 24, 171 CrossRefGoogle Scholar
Perlman, E. S., et al. 1999, AJ, 117, 2185 CrossRefGoogle Scholar
Telfer, R. C., Zheng, W., Kriss, G. A., & Davidsen, A. F. 2001, ApJ, in pressGoogle Scholar
Unwin, S. C., Wehrle, A. E., Urry, C. M., Gilmore, D. M., Barton, E. J., Kjerulf, B. C., Zensus, J. A., & Rabaca, C. R. 1994, ApJ, 432, 103 CrossRefGoogle Scholar
Wilson, A. S., & Colbert, E. J. M. 1995, ApJ, 438, 62 CrossRefGoogle Scholar