Barnali Das

VAST-MeMeS: a project to characterize radio emission from magnetic hot stars.

Magnetic hot stars are unique objects on the main-sequence that have large-scale magnetic fields of kG strength, which are stable throughout their lifetimes. Such characteristics make them ideal celestial laboratories to investigate magnetospheric physics. The magnetospheres of these stars emit over a wide range of frequencies including radio. The radio emission is non-thermal in nature and can be incoherent or coherent. While a lot of efforts have gone into characterizing these emission, especially in the optical band, characterization of their radio emission is yet to be accomplished. This is a critical limitation since radio is the primary magnetospheric signatures for magnetic late B and A type stars. Radio is also the band at which a number of similarities are observed between hot stars and cool stars/brown dwarfs with large-scale magnetic fields. The primary obstacle in characterzing radio emission is the small size of the sample of known radio-bright magnetic hot stars. In my talk, I will present the ‘VAST project to study Magnetic Massive Stars’ (VAST-MeMeS) that aims to take advantage of the enormous amount of radio data that the ASKAP telescope is collecting, in order to overcome this problem and answer key questions such as the driver of non-thermal emission. I will present our initial results and their implications towards recently reported model of radio emission from magnetic hot stars.