Revealing Companions to Nearby Stars with Astrometric Acceleration

Abstract

A subset of 51 Hipparcos astrometric binaries among FG dwarfs within 67 pc has been surveyed with the Near-Infrared Coronagraphic Imager adaptive optics system at Gemini-S, directly resolving for the first time 17 subarcsecond companions and 7 wider ones. Using these data together with published speckle interferometry of 57 stars, we compare the statistics of resolved astrometric companions with those of a simulated binary population. The fraction of resolved companions is slightly lower than expected from binary statistics. About 10% of astrometric companions could be "dark" (white dwarfs and close pairs of late M-dwarfs). To our surprise, several binaries are found with companions too wide to explain the acceleration. Re-analysis of selected intermediate astrometric data shows that some acceleration solutions in the original Hipparcos catalog are spurious.

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Document Details

Document Type
Technical Report
Publication Date
Jul 01, 2012
Accession Number
ADA573126

Entities

People

  • Andrei Tokovinin
  • Markus Hartung
  • Thomas L. Hayward
  • Valeri W. Makarov

Organizations

  • United States Naval Observatory

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Abstracts
  • Adaptive Optics
  • Catalogs
  • Data Mining
  • Data Science
  • Detection
  • Frequency
  • Information Science
  • Interferometry
  • Observatories
  • Optics
  • Simulations
  • Spearography
  • Standards
  • Stars
  • Statistics
  • Strehl Ratio

Fields of Study

  • Physics

Readers

  • Astronomy/Astrophysics