Polarization variability among Wolf-Rayet stars. II. Linear polarization of a complete sample of southern Galactic WN stars
1987; IOP Publishing; Volume: 322; Linguagem: Inglês
10.1086/165783
ISSN1538-4357
AutoresLaurent Drissen, Nicole St.-Louis, A. F. J. Moffat, Pierre Bastien,
Tópico(s)Astronomy and Astrophysical Research
Resumoview Abstract Citations (59) References (32) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Polarization Variability among Wolf-Rayet Stars. II. Linear Polarization as a Complete Sample of Southern Galactic WN Stars Drissen, Laurent ; St. -Louis, Nicole ; Moffat, Anthony F. J. ; Bastien, Pierre Abstract We present linear polarization data for the six brightest southern Wolf-Rayet (W-R) stars of the nitrogen sequence (WN), neglecting the peculiar WN 5 star HD 50896, which will be presented elsewhere. They are all of the cool WN 7, WN 8 subclasses, and all show intrinsic, apparently random, variations with amplitudes ranging from ΔP = 0.15% to 0.6%. The variations are probably caused by blobs of dense plasma being ejected in the wind. Combining these data with similar results for the seven brightest southern WC stars (Paper I), we find a general anticorrelation between the terminal velocity of the wind and the amplitude of the polarimetric variations. WC 9 and especially WN 8 stars show the largest amplitudes and thus have the least homogeneous winds. No obvious binary-type modulation is detected in the well-known, long-period, single-line WN 7(+O) binary HD 92740 nor in the WN 8 stars suspected of harboring compact companions, HD 86161 and HD 96548. From multicolor polarimetry, we find that the ratio of total visual to selective B - V extinction for three WNL stars in the Carina Nebula is normal, R = 3.0 ± 0.2. Publication: The Astrophysical Journal Pub Date: November 1987 DOI: 10.1086/165783 Bibcode: 1987ApJ...322..888D Keywords: Binary Stars; Linear Polarization; Stellar Winds; Variability; Wolf-Rayet Stars; Computational Astrophysics; Dense Plasmas; Early Stars; Electron Density (Concentration); Interstellar Extinction; Stellar Coronas; Stellar Luminosity; Astrophysics; POLARIZATION; STARS: BINARIES; STARS: WINDS; STARS: WOLF-RAYET full text sources ADS | data products SIMBAD (7) Related Materials (7) Part 1: 1987ApJ...322..870S 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
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