Scientific results from high-precision astrometry at the Palomar Testbed Interferometer

A new observing mode for the Palomar Testbed Interferometer was developed in 2002-2003 which enables differential astrometry at the level of 20 micro-arcseconds (μas) for binary systems with separations of several hundred milli-arcseconds (mas). This phase-referenced mode is the basis of the Palomar High-precision Astrometric Search for Exoplanet Systems (PHASES), a search for giant planets orbiting either the primary or secondary star in fifty binary systems. We present the first science results from the PHASES search. The properties of the stars comprising binary systems are determined to high precision. The mutual inclinations of several hierarchical triple star systems have been determined. We will present upper limits constraining the the existence of giant planets in a few of the target systems.

[1]  Maciej Konacki,et al.  An extrasolar giant planet in a close triple-star system , 2005, Nature.

[2]  Nicholas M. Elias,et al.  Navy Prototype Optical Interferometer Observations of the Double Stars Mizar A and Matar , 1998 .

[3]  European Southern Observatory,et al.  A purely geometric distance to the binary star Atlas, a member of the Pleiades , 2004 .

[4]  et al,et al.  The Palomar Testbed Interferometer , 1999 .

[5]  Michel Mayor,et al.  Multi-order TODCOR: Application to observations taken with the CORALIE echelle spectrograph - II. A planet in the system HD 41004 , 2004 .

[6]  Tel Aviv,et al.  Multi-order TODCOR: application to observations taken with the CORALIE echelle spectrograph I. The system HD 41004 ⋆,⋆⋆ , 2003 .

[7]  Gordon A. H. Walker,et al.  A Planetary Companion to γ Cephei A , 2003 .

[8]  Andrew F. Nelson,et al.  Planet Formation is Unlikely in Equal-Mass Binary Systems with a ~ 50 AU , 2000, astro-ph/0005451.

[9]  Andrei Tokovinin,et al.  Relative orientation of orbits in triple stars , 2002 .

[10]  Michel Mayor,et al.  The CORALIE survey for southern extra-solar planets. I. A planet orbiting the star Gliese 86 , 2000 .

[11]  A. Boss,et al.  Possible Rapid Gas Giant Planet Formation in the Solar Nebula and Other Protoplanetary Disks , 2000, The Astrophysical journal.

[12]  Benjamin F. Lane,et al.  PHASES Differential Astrometry and Iodine Cell Radial Velocities of the κ Pegasi Triple Star System , 2005, astro-ph/0509406.

[13]  Xiaopei Pan,et al.  A distance of 133–137 parsecs to the Pleiades star cluster , 2004, Nature.

[14]  E. Pfahl,et al.  Cluster Origin of the Triple Star HD 188753 and Its Planet , 2005, astro-ph/0509490.

[15]  Simon Portegies Zwart,et al.  Planets in triple star systems : The case of HD 188753 , 2005 .

[16]  et al.,et al.  The Visual Orbit of Pegasi , 1999 .

[17]  B. F. Lane,et al.  Differential Astrometry of Subarcsecond Scale Binaries at the Palomar Testbed Interferometer , 2004 .

[18]  Benjamin F. Lane,et al.  Phases differential astrometry and the mutual inclination of the v819 herculis triple star system , 2006 .

[19]  Benjamin F. Lane,et al.  PHASES High-Precision Differential Astrometry of δ Equulei , 2005, astro-ph/0507585.

[20]  Matthew Holman,et al.  Long-Term Stability of Planets in Binary Systems , 1996 .

[21]  Benjamin F. Lane,et al.  Phase-referenced Stellar Interferometry at the Palomar Testbed Interferometer , 2003 .