BH181

Dynamical Mass Measurement of A Brown Dwarf Binary System

Abstract

Direct mass measurement of brown dwarfs is critical for empirically constraining substellar evolutionary models. Dynamical mass measurement campaigns are ongoing and involve AO-assisted astrometric observations with 8-10m class telescopes and the HST. These data is used to determine the relative orbital parameters and hence total mass for the system. However, the absence of absolute orbital parameters precludes establishing the masses of the individual components of the system. We have detected the secondary component of the tight binary brown dwarf system 2MASS J07464256+2000321 in VLBI observations in March 2010. These results confirm that VLBI observations can be used to obtain the absolute orbit of the secondary component of this binary system, thereby confirming the mass of the individual components of the system to an accuracy of ~1%, the first time the has been achieved for brown dwarfs. We request 35 hours of HSA observations over the period of three years to determine the abso

Investigators

Name	Institution
Leon Harding	Galway, National University of Ireland
Walter Brisken	National Radio Astronomy Observatory
Adam Deller	Swinburne University of Technology
Quinn Konopacky	California at Los Angeles, University of
Stephen Bourke	Joint Institute for Very Long Baseline Interferometry European Research Infrastructure Consortium; Galway, National University of Ireland; Chalmers University of Technology; California Institute of Technology
Gregg Hallinan *	National Radio Astronomy Observatory; California at Berkeley, University of; California Institute of Technology
GBT Operator	Green Bank Observatory
vlbaops vlbaops	National Radio Astronomy Observatory
vlbiobs vlbiobs	National Radio Astronomy Observatory

* indicates the PI