Magnetic Activity on Late Type Stars and Brown Dwarfs
Gregg Hallinan (Caltech)
Magnetic Activity on Late Type Stars and Brown Dwarfs
Magnetic flares from active stars, particularly M dwarfs, will likely be the dominant class of transient detected by the LSST and may be prove to be a problematic foreground in efforts to detect fast extragalactic transients. Such flares result in higher X-ray and ultraviolet irradiation of orbiting planets and theoretical studies have suggested that the resulting photochemical reactions can lead to significant atmospheric loss. Terrestrial planets orbiting M dwarfs are likely the most abundant Earth-like planets in the solar neighborhood and understanding the impact of such activity is becoming increasingly important. Simultaneous detection of such flares with the LSST and widefield, low frequency radio telescopes will provide an unprecedented data-set for the study of such flares on active stars. LSST data will inform on the radiative output of flares, while low frequency radio bursts, analogous to those detected from the Sun, will inform on the density and speed of the associated interplanetary shocks. The LSST will also be a uniquely powerful for probing magnetic activity in brown dwarfs, in this case manifested via correlated optical and radio auroral emissions. These auroral emissions are currently the only probe of magnetic activity in the mass gap between planets and stars.
