Cool Stars 14 - Submitted Abstract # 290
This version created on 05 October 2006

Testing Stellar Evolutionary Models Through Interferometric Dynamical
Mass Determinations


Andy Boden, MSC/Caltech

Many models of stellar properties are in good agreement with the body
of precise stellar property determinations for stars near solar mass,
elemental abundance, and evolutionary state.  However, there are many
fewer empirical tests for stars far from solar properties, and
existing data in sectors such as low-mass and pre-main sequence stars
exhibits clear signs that modeling is in significant variance with the
data.  It is therefore important to expand the breadth of
observational constraints for stellar models to increase their
predictive power across the HR diagram.  Stars convert gravitational
potential energy to luminosity, so no stellar parameter is more
important than mass.  Mass is also the most difficult parameter to
measure -- typically accessible only through dynamical interactions in
general and measuring the three-dimensional (physical) orbits of
binary systems in particular.  Traditionally eclipsing binary systems
have provided the most important dynamical mass constraints, however,
the number of well-studied eclipsing systems is limited by the
required favorable geometry.  Attempting to broaden available
empirical constraints, over the past 15 years various astrometric
methods have made stellar parameter determinations with precisions
that are comparable to eclipsing system studies.  In my talk I will
review the contributions made by optical/near-IR interferometers such
as the MarkIII, HST FGS, NPOI, PTI, and KI.  I will also summarize my
view of the contributions interferometry might make in the near
future, including ongoing work at the VLTI, and eventual contributions
by the Space Interferometry Mission.  

----------------------------------