Two types of pulsating stars exist among stars with a mass between 1.5 and 2.5 solar masses: the delta Scuti stars and the gamma Dor stars. Theory tells us that, when such stars have a surface temperature between 6900 and 7400 Kelvin, they can have both types of pulsations, i.e. they are called “hybrid stars”. The NASA space mission Kepler provided a wealth of new candidate “hybrid stars”, even outside the theoretically predicted physical parameter range.
Coralie Neiner (LESIA, CNRS / Observatoire de Paris / UPMC / Université Paris Diderot) and Patricia Lampens (Royal Observatory of Belgium) have therefore sought which physical phenomena could mimic the hybrid character in delta Scuti stars. One possibility could be the presence of a magnetic field which would produce spots on the rotating stellar surface and mimic the gamma Dor pulsations. However, no magnetic field had ever been observed in a delta Scuti star until now…
Read the full story at Royal Observatory of Belgium News