Chapter

The AB Doradus System Revisited: The Dynamical Mass of AB Dor A

DOI: 10.1007/978-3-642-11250-8_13

ABSTRACT We report new radio interferometric observations of the quadruple pre-main-sequence (PMS) system ABD oradus. From these observations,
combined with existing VLT near-infrared relative astrometry, we have refined the estimates of the dynamical masses of the
system. In particular, we find component masses of 0.86 ± 0.09M⊙ and 0.090 ± 0.003M⊙ for ABD or A and ABD or C, respectively. These dynamical masses, coupled with temperatures and luminosities, allow for comparison
with theoretical stellar models. The case of ABDorC, in terms of calibration of evolutionary models of low-mass young stars
has been widely reported in previous studies. In this contribution, we compare the measured properties of ABDorA with several
solar-composition models for PMS stars. The models used in this comparison predict the dynamical mass to within the quoted
uncertainties.

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