J/AJ/159/214ivo://CDS.VizieR/J/AJ/159/214doi:10.26093/cds/vizier.51590214CDSFullard A.G.St-Louis N.Moffat A.F.J.Piirola V.E.Manset N.,Hoffman J.L.2021-12-07T21:19:33Z2020-07-21T09:19:33ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frwolf-rayet-starsmultiple-starssurveyspolarimetryvisible-astronomyWolf-Rayet (WR) stars have strong, hot winds, with mass-loss rates at least a factor of 10 greater than their O-star progenitors, although their terminal wind speeds are similar. In this paper, we use the technique of multiband linear polarimetry to extract information on the global asymmetry of the wind in a sample of 47 bright Galactic WR stars. Our observations also include time-dependent observations of 17 stars in the sample. The path to our goal includes removing the dominating component of wavelength-dependent InterStellar Polarization (ISP), which normally follows the well-known Serkowski law. We include a wavelength-dependent ISP position angle parameter in our ISP law and find that 15 stars show significant results for this parameter. We detect a significant component of wavelength-independent polarization due to electron scattering in the wind for 10 cases, with most WR stars showing none at the ~0.05% level precision of our data. The intrinsically polarized stars can be explained with binary interaction, large-scale wind structure, and clumping. We also found that 5 stars out of 19 observed with the Stromgren b filter (probing the complex {lambda}4600-4700{AA} emission-line region) have significant residuals from the ISP law and propose that this is due to wind asymmetries. We provide a useful catalog of ISP for 47 bright Galactic WR stars and upper limits on the possible level of intrinsic polarization.2020AJ....159..214Fhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/159/214CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toIII/215 : 7th Catalog of Galactic Wolf-Rayet stars (van der Hucht, 2001)I/345 : Gaia DR2 (Gaia Collaboration, 2018)J/AJ/120/2101 : Radial Velocity and Photometry of HD 104994 (Marchenko+, 2000)J/A+A/458/453 : Annex to 7th Cat. of Galactic WR Stars (van der Hucht, 2006)J/A+A/462/621 : UBVRI polarisation in NGC 5749 (Vergne+, 2007)J/A+A/471/165 : UBVRI polarisation in NGC 5606 (Orsatti+, 2007)J/ApJS/176/59 : FUSE survey of OVI in the disk of the Milky Way (Bowen+, 2008)J/A+A/531/A25 : Linear & circular polarisation spectra of 2 stars (Cox+,2011)J/AN/332/616 : V444 Cyg BV differential light curves (Eris+, 2011)J/A+A/556/A65 : LDN 1570 BV(RI)c polarisation & photometry (Eswaraiah+, 2013)J/A+A/608/A146 : Southern Hemis. ISMFORS2 spectropolarimetry (Bagnulo+, 2017)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/159/214https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/159/214http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/159/214https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/159/214https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/159/214http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/159/214GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/AJ/159/214/table3 (*Mean polarization data for all our targets)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/159/214/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/159/214/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/159/214/table3?GETtext/xml+votable180.050000true10.868321464.75982890.0055555555555555566/3616 3723 12942 14255 14259 14309 14411 14619 14629-14631 14640-14641 14646 14649 14788 15506 20764 28726 28916 29090 29097 29513 30231 37232 37333 37343 37370 37863 37923-37924 38016 38019 39709 39755 41419 41570 41630 41745 42295-42296 42394 42405 42481 43042 43075https://cdsarc.cds.unistra.fr/viz-bin/moc/J/AJ/159/214?format=asciiOpticaldefaultJ/AJ/159/214/table3*Mean polarization data for all our targetsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWR[1/157] WR catalog number (WR N)meta.id;meta.mainintVarVariability source (1)meta.code;src.varcharMeanMean fit typemeta.notecharNum[1/71] Number of observationsmeta.numberintHJD[7760/8418]? Heliocentric Julian Date; HJD-2440000dtime.epochdoublenullableBandObserved bandinstr.bandpasscharq[-6.45/2.47] Percent Stokes Q/I%phys.polarization.stokesfloate_q[0.005/0.52] Error in q%stat.errorfloatu[-6.7/4.28] Percent Stokes U/I%phys.polarization.stokesfloate_u[0.005/0.52] Error in u%stat.errorfloatNobsNumber of observation for each target (link to tablea1)meta.numberintnullableSimbadSimbad column added by the CDSmeta.ref.urlchar_RAPosition from Simbad (right ascension part)degpos.eq.ra;meta.main_DEPosition from Simbad (declination part)degpos.eq.dec;meta.mainJ/AJ/159/214/tablea1*Observational data for objects with fewer than 5 observationsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWR[16/113] WR catalog designation (WR N)meta.id;meta.mainintHJD[410/418] Heliocentric Julian date; HJD-2440000 (1)dtime.epochdoubleUq[-3.22/-0.06] U band q polarization%phys.polarization.stokesfloatUu[-0.92/1.1] U band u polarization%phys.polarization.stokesfloate_Uq[0.01/0.21] Error in Uq%stat.errorfloatBq[-2.64/-0.02] B band q polarization%phys.polarization.stokesfloatBu[-1.13/1.07] B band u polarization%phys.polarization.stokesfloate_Bq[0.01/0.12] Error in Bq%stat.errorfloatVq[-2.61/-0.02] V band q polarization%phys.polarization.stokesfloatVu[-1.28/1.13] V band u polarization%phys.polarization.stokesfloate_Vq[0.01/0.11] Error in Vq%stat.errorfloatRq[-2.49/0.16] R band q polarization%phys.polarization.stokesfloatRu[-1.43/1.09] R band u polarization%phys.polarization.stokesfloate_Rq[0.009/0.21] Error in Rq%stat.errorfloatbq[-1.37/-0.16]? b band q polarization%phys.polarization.stokesfloatnullablebu[-1.13/0.48]? b band u polarization%phys.polarization.stokesfloatnullablee_bq[0.01/0.09]? Error in bq%stat.errorfloatnullableHJDb[410/418]? Heliocentric Julian date of b band; HJD-2440000 (1)dtime.epochdoublenullableJ/AJ/159/214/tablea2Polarimetric observations of WR 133, observed at the Crimean ObservatoryrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJD[320/889] Heliocentric Julian date; HJD-2447000dtime.epochfloatUq[-0.12/0.68] U band q polarization%phys.polarization.stokesfloate_Uq[0.003/0.31] Error in Uq%stat.errorfloatUu[-0.9/0.15] U band u polarization%phys.polarization.stokesfloate_Uu[0.01/0.21] Error in Uu%stat.errorfloatBq[0.06/0.57] B band q polarization%phys.polarization.stokesfloate_Bq[0.009/0.1] Error in Bq%stat.errorfloatBu[-0.46/0.05] B band u polarization%phys.polarization.stokesfloate_Bu[0.006/0.13] Error in Bu%stat.errorfloatVq[0.03/0.47] V band q polarization%phys.polarization.stokesfloate_Vq[0.008/0.1] Error in Vq%stat.errorfloatVu[-0.49/0.001] V band u polarization%phys.polarization.stokesfloate_Vu[0.01/0.08] Error in Vu%stat.errorfloatRq[0.08/0.45] R band q polarization%phys.polarization.stokesfloate_Rq[0.01/0.1] Error in Rq%stat.errorfloatRu[-0.42/-0.03] R band u polarization%phys.polarization.stokesfloate_Ru[0.01/0.1] Error in Ru%stat.errorfloatIq[-0.04/0.42] I band q polarization%phys.polarization.stokesfloate_Iq[0.006/0.08] Error in Iq%stat.errorfloatIu[-0.37/-0.007] I band u polarization%phys.polarization.stokesfloate_Iu[0.01/0.15] Error in Iu%stat.errorfloatJ/AJ/159/214/tablea3Polarimetric observations of WR 134, observed at the Crimean Observatory.recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJD[59/74] Heliocentric Julian date; HJD-2447700dtime.epochfloatUq[0.94/1.5] U band q polarization%phys.polarization.stokesfloate_Uq[0.03/0.11] Error in Uq%stat.errorfloatUu[0.13/0.47] U band u polarization%phys.polarization.stokesfloate_Uu[0.02/0.12] Error in Uu%stat.errorfloatBq[0.79/1.15] B band q polarization%phys.polarization.stokesfloate_Bq[0.02/0.06] Error in Bq%stat.errorfloatBu[0.07/0.34] B band u polarization%phys.polarization.stokesfloate_Bu[0.01/0.08] Error in Bu%stat.errorfloatVq[0.85/1.27] V band q polarization%phys.polarization.stokesfloate_Vq[0.03/0.07] Error in Vq%stat.errorfloatVu[0.1/0.4] V band u polarization%phys.polarization.stokesfloate_Vu[0.01/0.09] Error in Vu%stat.errorfloatRq[0.68/1] R band q polarization%phys.polarization.stokesfloate_Rq[0.02/0.09] Error in Rq%stat.errorfloatRu[0.03/0.25] R band u polarization%phys.polarization.stokesfloate_Ru[0.01/0.09] Error in Ru%stat.errorfloatIq[0.61/0.9] I band q polarization%phys.polarization.stokesfloate_Iq[0.01/0.08] Error in Iq%stat.errorfloatIu[-0.06/0.24] I band u polarization%phys.polarization.stokesfloate_Iu[0.02/0.07] Error in Iu%stat.errorfloat