We obtained definitive magnetic field measurements for flare stars, finding magnetic fluxes over 100 times larger than what is seen on the Sun. With two years of data, we still see no magnetic variations, which has important ramifications for the underlying dynamo. Magnetic fields are believed to play a crucial role in accretion onto young stars, and we recently obtained one of the only magnetic field measurements for this important class of stars. In the coming months, we will use Phoenix to measure magnetic fields on active F, G, and K dwarfs, which can only be done accurately using a high resolution infrared spectrometer. Because we are interested in relatively cool stars, we have incorporated into the code an equation of state that includes molecules.
Several stars show unusual fluorescent emission by very hot molecular hydrogen.
It is also clear now that accretion, not stellar activity, plays a key role in producing the UV emission. I have been studying the late stage of stellar evolution, where the physics of mass loss remains poorly understood. Graham Harper and I have put together a radiative transfer code that handles departures from non-LTE, spherical geometery, outflows, and realistic scattering. This is the first code with all of the pieces needed to model resonance lines in winds, measure meaningful mass loss rates, and constrain the wind acceleration mechanism. Finally, I have become involved with a project led by Mark Giampapa at NOAO to study line bisectors in stars stars with reported planets.