Precision Millimeter Astrometry of the α Centauri AB System

  title={Precision Millimeter Astrometry of the $\alpha$ Centauri AB System},
  author={Rachel L. Akeson and Charles A. Beichman and Pierre Kervella and Edward Fomalont and G. Fritz Benedict},
  journal={The Astronomical Journal},
Alpha Centauri A is the closest solar-type star to the Sun and offers the best opportunity to find and ultimately to characterize an Earth-sized planet located in its habitable zone. Here, we describe initial results from an Atacama Large Millimeter/submillimeter Array (ALMA) program to search for planets in the α Cen AB system using differential astrometry at millimeter wavelengths. Our initial results include new absolute astrometric measurements of the proper motion, orbital motion and… 

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