Magnetic stars with wide depressions in the continuum. 2. The silicon star with a complex field structure HD 27404

Abstract

Observations of the chemically peculiar star HD 27404 with the 6-m SAO RAS telescope showed a strong magnetic field with the longitudinal field component varying in a complicated way in the range of −2.5 to 1 kG. Fundamental parameters of the star (T_eff = 11 300 K, log g = 3.9) were estimated analyzing photometric indices in the Geneva and in the Stro¨ mgren–Crawford photometric systems. We detected weak radial velocity variations which can be due to the presence of a close star companion or chemical spots in the photosphere. Rapid estimation of the key chemical element abundance allows us to refer HD 27404 to a SiCr or Si+ chemically peculiar A0–B9 star.