Speaker
Federico Spada
(Leibniz-Institut fuer Astrophysik Potsdam (AIP))
Description
A long-standing issue in the theory of low mass stars is the disagreement between the
theoretical and observed mass-radius-Teff relationships. Stellar models
systematically underpredict stellar radii by ~10% and overpredict effective
temperatures at the ~5% level. Interestingly, the two effects compensate each other
to give approximately the same luminosity, suggesting a surface origin for the
phenomenon. Although this disagreement is sometimes ascribed to non-intrinsic causes,
an intriguing possibility is that the inflated radii of these stars could be a
manifestation of their magnetic activity. The 'radius discrepancy' phenomenon is
discussed in the context of up-to-date stellar models, compared with the most
accurate observational data currently available. Preliminary models taking into
account the effect of magnetic fields on the stellar structure
will also be presented.
Primary authors
Alison Sills
(Department of Physics and Astronomy, McMaster University, Hamilton, Canada)
Federico Spada
(Leibniz-Institut fuer Astrophysik Potsdam (AIP))
Pierre Demarque
(Department of Astronomy, Yale University, New Haven, USA)
Yong-Cheol Kim
(Astronomy Department, Yonsei University, Seoul, South Korea)
