Abstract

Directly imaged planets and brown dwarfs are critical tools for studying the formation, evolution, and atmospheric physics of wide-separation substellar objects. Dynamical masses of these objects are especially important because they enable robust tests of cooling models.  However, these measurements are rare because they require the detection of reflex motion from the host star.  Our goal is to dramatically improve the scope and precision of these tests by targeting stars exhibiting small proper motion differences between Hipparcos and Gaia EDR3 that confer the presence of unseen substellar companions. Over the past two years, we have launched a multi-facility, systematic high-contrast imaging survey of the accelerating stars most likely to harbor long-period giant planets and brown dwarfs. In this talk, I will present an overview of our program, our novel approach to efficient target selection, and early results including the first discovery from this survey.