J/A+A/586/A87ivo://CDS.VizieR/J/A+A/586/A87doi:10.26093/cds/vizier.35860087CDSKostogryz N.M.Milic I.Berdyugina S.V.Hauschildt P.H.2016-01-28T08:26:09Z2016-01-28T09:03:02ZCDS support team

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

cds-question@unistra.frastronomical-modelsstellar-atmospherespolarimetrylate-type-starsOne of the necessary parameters needed for the interpretation of the light curves of transiting exoplanets or eclipsing binary stars (as well as interferometric measurements of a star or microlensing events) is how the intensity and polarization of light changes from the center to the limb of a star. Scattering and absorption processes in the stellar atmosphere affect both the center-to-limb variation of intensity (CLVI) and polarization (CLVP). In this paper, we present a study of the CLVI and CLVP in continuum spectra, taking into consideration the different contributions of scattering and absorption opacity for a variety of spectral type stars with spherical atmospheres. We solve the radiative transfer equation for polarized light in the presence of a continuum scattering, taking into consideration the spherical model of a stellar atmosphere. To cross-check our results, we developed two independent codes that are based on Feautrier and short characteristics methods, respectively, We calculate the center-to-limb variation of intensity (CLVI) and polarization (CLVP) in continuum for the Phoenix grid of spherical stellar model atmospheres for a range of effective temperatures (4000-7000K), gravities (logg=1.0-5.5), and wavelengths (4000-7000{AA}). In addition, we present several tests of our codes and compare our calculations for the solar atmosphere with published photometric and polarimetric measurements. We also show that our two codes provide similar results in all considered cases.2016A&A...586A..87Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/586/A87CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/A+A/575/A89 : Center-to-limb polarization of FGK stars (Kostogryz+, 2015)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/586/A87https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/586/A87http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/586/A87https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/586/A87https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/586/A87http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/586/A87GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapdefaultJ/A+A/586/A87/table1Calculated center-to-limb variation of intensity for different stellar parametersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintlambda[4000/7000] Wavelength0.1nmem.wlintTeff[4000/7000] Effective temperatureKphys.temperature.effectiveintlogg[1/5.5] Surface gravityphys.gravityfloatPlotPlot the limb-darkening profile for the specified Teff, loggmeta.ref.urlcharmulimb[0.03/0.37] Position of the stellar limbstat.paramfloatRstarCalculated stellar radiuskmphys.size.radius;meta.modelledfloatLD01[0/1] Limb darkening at {mu}=0.01, I(mu)/I(1.0)phot.limbDarkdoubleLD04[0/1] Limb darkening at {mu}=0.04, I(mu)/I(1.0)phot.limbDarkdoubleLD09[0/1] Limb darkening at {mu}=0.09, I(mu)/I(1.0)phot.limbDarkdoubleLD16[0/1] Limb darkening at {mu}=0.16, I(mu)/I(1.0)phot.limbDarkdoubleLD24[0/1] Limb darkening at {mu}=0.24, I(mu)/I(1.0)phot.limbDarkdoubleLD35[0/1] Limb darkening at {mu}=0.35, I(mu)/I(1.0)phot.limbDarkdoubleLD46[0/1] Limb darkening at {mu}=0.46, I(mu)/I(1.0)phot.limbDarkdoubleLD58[0/1] Limb darkening at {mu}=0.58, I(mu)/I(1.0)phot.limbDarkdoubleLD72[0/1] Limb darkening at {mu}=0.72, I(mu)/I(1.0)phot.limbDarkdoubleLD86[0/1] Limb darkening at {mu}=0.86, I(mu)/I(1.0)phot.limbDarkdoubleJ/A+A/586/A87/table2Calculated center-to-limb variation of polarization for different stellar parameterslambda[4000/7000] Wavelength0.1nmem.wlintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintTeff[4000/7000] Effective temperatureKphys.temperature.effectiveintlogg[1/5.5] Surface gravityphys.gravityfloatPlotPlot the limb-darkening profile for the specified Teff, loggmeta.ref.urlcharmulimb[0.03/0.37] Position of the stellar limbstat.paramfloatLD01[0/1] Limb darkening at {mu}=0.01, I(mu)/I(1.0)phot.limbDarkdoubleLD04[0/1] Limb darkening at {mu}=0.04, I(mu)/I(1.0)phot.limbDarkdoubleLD09[0/1] Limb darkening at {mu}=0.09, I(mu)/I(1.0)phot.limbDarkdoubleLD16[0/1] Limb darkening at {mu}=0.16, I(mu)/I(1.0)phot.limbDarkdoubleLD24[0/1] Limb darkening at {mu}=0.24, I(mu)/I(1.0)phot.limbDarkdoubleLD35[0/1] Limb darkening at {mu}=0.35, I(mu)/I(1.0)phot.limbDarkdoubleLD46[0/1] Limb darkening at {mu}=0.46, I(mu)/I(1.0)phot.limbDarkdoubleLD58[0/1] Limb darkening at {mu}=0.58, I(mu)/I(1.0)phot.limbDarkdoubleLD72[0/1] Limb darkening at {mu}=0.72, I(mu)/I(1.0)phot.limbDarkdoubleLD86[0/1] Limb darkening at {mu}=0.86, I(mu)/I(1.0)phot.limbDarkdouble