High-Resolution Spectroscopy of some Active Southern Stars

Ian A. Waite, Brad D. Carter, Stephen C. Marsden and Matthew W. Mengel

Abstract

High-resolution échelle spectra of 42 nearby southern solar-type stars have been obtained, in a search for young, single, active, and rapidly rotating sun-like stars suitable for Doppler imaging and Zeeman Doppler imaging studies. As a result of this survey, 13 stars were determined to be youthful with ages less than 600 Myr (Hyades age) and eight of these were found to have projected rotational velocities in excess of 15 km s^–1. In addition, five spectroscopic binary systems were identified. Of those stars observed for this survey, HD 106506 is the most outstanding target for mapping active regions. It is an apparently young and single star with rapid rotation (v sin i ~ 80 km s^–1), strong Hα chromospheric activity (log R′_Hα ~ –4.2), and deformation of the spectral line profiles indicating the presence of large starspots.

Keywords: stars: activity — stars: spots — stars: magnetic fields — stars: rotation

Publications of the Astronomical Society of Australia 22(1) 29 - 35  doi:10.1071/AS04058