Speaker
Jeremy Jones
(Georgia State University)
Description
The rapid rotation of A-stars introduces two major difficulties when isochrone dating them. The oblateness and gravity darkening induced by rapid rotation affects the shape and temperature profile of the star. This rotation also changes how the star evolves and must be accounted for when choosing evolution models for comparison. Interferometric observations can address this first concern and modern evolutionary models that account for rotation can address the second concern. When used in conjunction, these yield accurate age estimates for rapidly rotating A-stars. Using observations from the CHARA Array and the MESA evolutionary models, we estimate the ages and masses of seven members of the coeval Ursa Major moving group. We also estimate the age of the directly-imaged planet host star kappa Andromedae with implications for the mass of its companion. Finally, I present new observations and preliminary age estimates for four stars with the lambda Bootis chemical peculiarity.
Primary author
Jeremy Jones
(Georgia State University)
