J/ApJ/905/157ivo://CDS.VizieR/J/ApJ/905/157doi:10.26093/cds/vizier.19050157CDSVaillancourt J.E.Andersson B.-G.Clemens D.P.Piirola V.Hoang T.,Becklin E.E.Caputo M.2022-08-29T10:11:47Z2022-08-08T09:13:06ZCDS support team

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

cds-question@unistra.frmolecular-cloudspolarimetryinterstellar-mediumextinctionstellar-spectral-typesvisible-astronomyinfrared-sourcesThe optical and near-infrared (OIR) polarization of starlight is typically understood to arise from the dichroic extinction of that light by dust grains whose axes are aligned with respect to a local magnetic field. The size distribution of the aligned-grain population can be constrained by measurements of the wavelength dependence of the polarization. The leading physical model for producing the alignment is that of radiative alignment torques (RATs), which predicts that the most efficiently aligned grains are those with sizes larger than the wavelengths of light composing the local radiation field. Therefore, for a given grain-size distribution, the wavelength at which the polarization reaches a maximum ({lambda}_max_) should correlate with the characteristic reddening along the line of sight between the dust grains and the illumination source. A correlation between {lambda}_max_ and reddening has been previously established for extinctions up to A_V_~4mag. We extend the study of this relationship to a larger sample of stars in the Taurus cloud complex, including extinctions A_V_>10mag. We confirm the earlier results for A_V_~4mag but find that the {lambda}_max_ versus A_V_ relationship bifurcates above A_V_~4mag, with part of the sample continuing the previously observed relationship. The remaining sample exhibits a steeper rise in {lambda}_max_ versus A_V_. We propose that the data exhibiting the steep rise represent lines of sight of high-density "clumps," where grain coagulation has taken place. We present RAT-based modeling supporting these hypotheses. These results indicate that multiband OIR polarimetry is a powerful tool for tracing grain growth in molecular clouds, independent of uncertainties in the dust temperature and emissivity.2020ApJ...905..157Vhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/905/157CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toIII/92 : A Library of Stellar Spectra (Jacoby+ 1984)V/73 : Emission-Line Stars of the Orion Population (Herbig+ 1988)I/259 : The Tycho-2 Catalogue (Hog+ 2000)III/231 : The Tycho-2 Spectral Type Catalog (Wright+, 2003)I/297 : NOMAD Catalog (Zacharias+ 2005)II/349 : The Pan-STARRS release 1 (PS1) Survey - DR1 (Chambers+, 2016)II/336 : AAVSO Photometric All Sky Survey (APASS) DR9 (Henden+, 2016)I/347 : Distances to 1.33 billion stars in Gaia DR2 (Bailer-Jones+, 2018)I/345 : Gaia DR2 (Gaia Collaboration, 2018)V/154 : Sloan Digital Sky Surveys (SDSS), Release 16 (DR16) (Ahumada+, 2020)J/AJ/130/873 : Properties of BQS objects in the SDSS DR3 area (Jester+, 2005)J/ApJ/665/369 : Photopolarimetry of Southern Coalsack stars (Andersson+, 2007)J/A+A/492/277 : Analysis of Collinder 69 stars with VOSA (Bayo+, 2008)J/ApJS/176/457 : Taurus dark cloud background star catalog (Shenoy+, 2008)J/A+A/502/845 : Dust coagulation in molecular clouds (Ormel+, 2009)J/ApJS/186/259 : Taurus Spitzer survey: new candidate members (Rebull+, 2010)J/ApJS/196/4 : New young star candidates in Taurus-Auriga (Rebull+, 2011)J/ApJ/741/21 : Polarization of stars in Taurus (Chapman+, 2011)J/ApJ/786/97 : Photospheric properties of T Tauri stars (Herczeg+, 2014)J/ApJ/849/157 : Polarimetry obs. toward IC5146 background stars (Wang+, 2017)J/A+A/630/A137 : Structure and kinematics of the Taurus region (Galli+, 2019)J/MNRAS/510/6085 : Magnetic field of Taurus/B211 (Li+, 2022)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/905/157https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/905/157http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/905/157https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/905/157https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/905/157http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/905/157GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/905/157/table1 (NOT/TurPol sources)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/905/157/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/905/157/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/905/157/table1?GETtext/xml+votable180.050000true60.56333327.1768610.005555555555555556Cone search capability for table J/ApJ/905/157/table2 (Stellar target for optical spectropolarimetry)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/905/157/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/905/157/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/905/157/table2?GETtext/xml+votable180.050000true62.25583324.8892780.0055555555555555565/262 274 292 6/375 1031 1036 1039-1040 1042 1044-1046 1052-1053 1055 1061 1066-1068 1070-1071 1075 1077-1079 1082-1086 1088 1120 1152 1154 1157-1161 1164 1166-1167 1174 1176 1178https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/905/157?format=asciiOpticalInfrareddefaultJ/ApJ/905/157/table1NOT/TurPol sourcesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar namemeta.id;meta.maincharprimaryRAJ2000[4] Hour of right ascension (J2000)pos.eq.ra;meta.mainDEJ2000[22/29] Degree of declination (J2000)pos.eq.dec;meta.mainVmag[6.3/11.4] V magnitude from SIMBADmagphot.mag;em.opt.VfloatRatio[1.6/6.7] Total-to-selective extinction ratio (R_V_)phys.absorption.gal;arith.ratiofloate_Ratio[0.25/5.33] Ratio uncertainty ({sigma}_RV_)stat.error;arith.ratiofloatAv[0.58/2.82] Visual extinctionmagphys.absorptionfloate_Av[0.06/0.17] Av uncertaintymagstat.errorfloatStdDisplay the measurements for this standard high-polarization stars for Kast (link to Table 9)meta.ref.urlintnullablePlotInteractive plot of polarization amplitudemeta.ref.urlcharHPInteractive plot of polarization amplitudemeta.ref.urlcharSimbadSimbad column added by the CDSmeta.ref.urlcharJ/ApJ/905/157/table2Stellar target for optical spectropolarimetrySimbadNameSimbad column added by the CDSmeta.idcharnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar name ("SWIWNNN" ; "NNN"=recno in Shenoy+ 2008, J/ApJS/176/457)meta.id;meta.maincharONameOther name(s)meta.idcharRAJ2000[4] Hour of right ascension (J2000)pos.eq.ra;meta.mainDEJ2000[22/30] Degree of declination (J2000)pos.eq.dec;meta.mainVmag[10.9/17.1] V-band brightnesses from the NOMAD compilationmagphot.mag;em.opt.VfloatSpTSpectral type estimated from this work (1)src.spTypecharAv[1.3/9.1]? Visural extinction from Shenoy+ (2008, J/ApJS/176/457)magphys.absorptionfloatnullablee_Av[0.5/0.9]? Av uncertaintymagstat.errorfloatnullableRatio1[2.3/12.2]? Extinction ratio (R_V_=1.1*E(V-K)/E(B-V)) (2)magphys.absorption.gal;arith.ratiofloatnullablee_Ratio1[0.1/2]? Ratio1 uncertaintymagstat.errorfloatnullableRatio2[2.1/11]? Extinction ratio, R_V_ (3)magphys.absorption.gal;arith.ratiofloatnullablee_Ratio2[0.1/3.1]? Ratio2 uncertaintymagstat.errorfloatnullableRefSource of visual photometry (4)meta.bibcharDist[131/3355] Distance from Gaia DR2pcpos.distance;pos.heliocentricinte_Dist[1/710] Lower uncertainty on Distpcstat.errorintE_Dist[1/1015] Upper uncertainty on Distpcstat.error;stat.maxintNspNumber of spectropolarimetry measurements for this star (link to Table 4)meta.numberintnullablePlotInteractive plot of polarization amplitudemeta.ref.urlcharNOMADDisplay data from NOMAD cat. (I/297) within 3"meta.ref.urlcharAAVSODisplay data from AAVSO cat. (II/336) within 2"meta.ref.urlcharPS1Display data from PS1 cat. (II/349) within 2"meta.ref.urlcharSDSSDisplay data from SDSS-DR16 cat. (V/154) within 0.5"meta.ref.urlcharSloanDisplay the online SDSS-DR16 data for the nearest objectmeta.ref.urlcharJ/ApJ/905/157/table3Photo-polarimetry results from the low-extinction sampleNameStar namemeta.id;meta.maincharprimarye_q[0.01/0.15] Uncertainty in q%stat.errordoublerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintlambda[0.36/0.83] Wavelength of bin center (1)umem.wlfloatq[-3.21/2.8] q Stokes parameter q=Q/I%phys.polarization.stokes;arith.ratiofloatu[-2.33/5.6] u Stokes parameter u=U/I%phys.polarization.stokes;arith.ratiofloate_u[0.01/0.15] Uncertainty in u%stat.errordoublep[0/6.25] Polarization amplitude, corrected for positive bias%phys.polarizationfloate_p[0.01/0.15] Uncertainty in p%stat.errordoublePA[0.2/179.4]? Polarization Angle ({theta}); east of north (G1)degpos.posAng;phys.polarizationfloatnullablee_PA[0.09/9.42]? Uncertainty in PA ({sigma}_{theta}_) (G1)degstat.errordoublenullableJ/ApJ/905/157/table4Spectropolarimetry and H-band results for the high-extinction samplee_u[0.069/7.4] Uncertainty in u%stat.errordoublep[0/7.85] Polarization amplitude, corrected for positive bias%phys.polarizationfloate_p[0.069/6.4] Uncertainty in p%stat.errordoublePA[0/175.2]? Polarization Angle ({theta}); east of north (G1)degpos.posAng;phys.polarizationfloatnullablee_PA[0.3/21.2]? Uncertainty in PA ({sigma}_{theta}_) (G1)degstat.errordoublenullablechi2[0/86] Reduced chi-squared of polarization fit (2)stat.fit.chi2;phys.polarization;meta.modelleddoublerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar namemeta.id;meta.maincharlambda[0.48/1.63] Wavelength of bin center (1)umem.wlfloatq[-5.62/7.23] q Stokes parameter q=Q/I%phys.polarization.stokes;arith.ratiofloate_q[0.069/6.4] Uncertainty in q%stat.errordoubleu[-5.12/7.9] u Stokes parameter u=U/I%phys.polarization.stokes;arith.ratiofloatJ/ApJ/905/157/table9Standard high-polarization stars for Kaste_u[0.079/0.72] Uncertainty in u%stat.errordoubleu[2.75/5.81] u Stokes parameter u=U/I%phys.polarization.stokes;arith.ratiofloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar namemeta.id;meta.maincharn_NameStar name (1)meta.notecharlambda[0.485/0.985] Wavelength of bin center (2)umem.wlfloatq[-2.94/2.71] q Stokes parameter q=Q/I%phys.polarization.stokes;arith.ratiofloate_q[0.079/0.72] Uncertainty in q%stat.errordoublep[2.86/6.36] Polarization amplitude, corrected for positive bias%phys.polarizationfloate_p[0.079/0.71] Uncertainty in p%stat.errordoublePA[32/65.5] Polarization Angle ({theta}); east of northdegpos.posAng;phys.polarizationfloate_PA[0.38/3.8] Uncertainty in PA ({sigma}_{theta}_)degstat.errordoublechi2[0.033/12] Reduced chi-squared of polarization fitstat.fit.chi2;phys.polarization;meta.modelleddouble