Chemical spots and their dynamical evolution on HgMn stars

TL;DR

This paper reports the discovery of rapid chemical spot evolution and magnetic fields on HgMn stars, challenging previous assumptions about their static surface features and non-magnetic nature.

Contribution

It presents the first evidence of fast dynamical evolution of chemical spots and magnetic fields on HgMn stars, revealing new physical processes in these radiative stars.

Findings

Chemical spots on HgMn stars evolve rapidly.

Magnetic fields are present on HgMn stars previously thought non-magnetic.

New observational evidence of magnetic fields on AR Aur.

Abstract

Our recent studies of late B-type stars with HgMn peculiarity revealed for the first time the presence of fast dynamical evolution of chemical spots on their surfaces. These observations suggest a hitherto unknown physical process operating in the stars with radiative outer envelopes. Furthermore, we have also discovered existence of magnetic fields on these stars that have up to now been thought to be non-magnetic. Here we will discuss the dynamical spot evolution on HD 11753 and our new results on magnetic fields on AR Aur.