Polarization variability among Wolf-Rayet stars. I. Linear polarization of a complete sample of southern Galactic WC stars

Abstract

view Abstract Citations (102) References (58) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Polarization Variability among Wolf-Rayet Stars. I. Linear Polarization of a Complete Sample of Southern Galactic WC Stars St. -Louis, Nicole ; Drissen, Laurent ; Moffat, Anthony F. J. ; Bastien, Pierre ; Tapia, Santiago Abstract As the first in a series of investigations on polarization variability of Wolf-Rayet (W-R) stars, this paper presents extensive time-dependent linear polarization observations of the seven known southern W-R stars of the carbon sequence brighter than magnitude b = 9. The results can be grouped into three categories: (1) three single-line stars, for which the observed stochastic variability in polarization decreases dramatically for stars with faster winds; the additional fact that the polarization vector of the nonvarying WC 7 star HD 156385 matches the interstellar polarization vector suggests that its wind is highly homogeneous, spherically symmetric, and very stable in time; (2) two short-period WC + O V binaries which show double-wave orbital modulation with very low residuals as expected from (1) for fast winds; and (3) two relatively long-period WC + O I binaries in which the effects of nonradial pulsations of the bright supergiants are important compared to the binary modulation. Publication: The Astrophysical Journal Pub Date: November 1987 DOI: 10.1086/165782 Bibcode: 1987ApJ...322..870S Keywords: Binary Stars; Linear Polarization; Southern Sky; Stellar Winds; Wolf-Rayet Stars; Companion Stars; Supergiant Stars; Tables (Data); Time Dependence; Astrophysics; POLARIZATION; STARS: BINARIES; STARS: WINDS; STARS: WOLF-RAYET full text sources ADS | data products SIMBAD (7) Related Materials (7) Part 2: 1987ApJ...322..888D Part 3: 1988ApJ...330..286S Part 4: 1989ApJ...343..902R Part 5: 1989ApJ...347.1034R Part 6: 1990ApJ...359..211R Part 7: 1992ApJ...386..288D Part 8: 1993ApJ...413..724M