8-12 juin, 2014


Beam me up, Spotty: Toward a new understanding of the structure of massive star photospheres

Alexandre David-Uraz (Queen's University/Royal Military College)

G. Wade (Royal Military College) S. Owocki (University of Delaware) O. Kochukhov (Uppsala University)

For the past 30 years, cyclical wind variability in hot massive stars has puzzled the astronomical community. While phenomenological models involving wind structures driven by co-rotating bright spots have been proposed to explain the observed variations, the underlying physics remains to this day a mystery. I will present recent results from empirical models and numerical hydrodynamics simulations constraining the properties of bright spots in OB star photospheres. These will be compared to spot characteristics recently inferred from high-precision MOST photometry, and to wind structures inferred from UV spectroscopic monitoring. Finally, I will explore the possibility that such spots are associated with small-scale magnetic fields and discuss the detectability of such fields.
(doit être confirmé par le SOC)