First results from the LIFE project: discovery of two magnetic hot evolved stars

Abstract

We present the initial results of the Large Impact of magnetic Fields on the\nEvolution of hot stars (LIFE) project. The focus of this project is the search\nfor magnetic fields in evolved OBA giants and supergiants with visual\nmagnitudes between 4 and 8, with the aim to investigate how the magnetic fields\nobserved in upper main sequence (MS) stars evolve from the MS until the late\npost-MS stages. In this paper, we present spectropolarimetric observations of\n15 stars observed using the ESPaDOnS instrument of the CFHT. For each star, we\nhave determined the fundamental parameters and have used stellar evolution\nmodels to calculate their mass, age and radius. Using the LSD technique, we\nhave produced averaged line profiles for each star. From these profiles, we\nhave measured the longitudinal magnetic field strength and have calculated the\ndetection probability. We report the detection of magnetic fields in two stars\nof our sample: a weak field of $B_l=1.0\\pm0.2\\,$G is detected in the post-MS A5\nstar 19$\\,$Aur and a stronger field of $B_l=-230\\,\\pm\\,10\\,$G is detected in\nthe MS/post-MS B8/9 star HR$\\,$3042.\n