J/ApJ/849/157ivo://CDS.VizieR/J/ApJ/849/157doi:10.26093/cds/vizier.18490157CDSWang J.-W.Lai S.-P.Eswaraiah C.Clemens D.P.Chen W.-P.Pandey A.K.2019-11-11T22:00:00Z2018-07-19T13:56:27ZCDS support team

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

cds-question@unistra.frpolarimetryvisible-astronomyinfrared-photometryextinctionstar-forming-regionsinterstellar-mediumWe present optical and near-infrared stellar polarization observations toward the dark filamentary clouds associated with IC5146. The data allow us to investigate the dust properties (this paper) and the magnetic field structure (Paper II). A total of 2022 background stars were detected in the Rc, i', H, and/or K bands to A_V_<~25mag. The ratio of the polarization percentage at different wavelengths provides an estimate of {lambda}_max_, the wavelength of the peak polarization, which is an indicator of the small-size cutoff of the grain size distribution. The grain size distribution seems to significantly change at A_V_~3mag, where both the average and dispersion of P_Rc_/P_H_ decrease. In addition, we found {lambda}_max_~0.6-0.9{mu}m for A_V_>2.5mag, which is larger than the ~0.55{mu}m in the general interstellar medium (ISM), suggesting that grain growth has already started in low-AV regions. Our data also reveal that polarization efficiency (PE=P_{lambda}_/A_V_) decreases with A_V_ as a power law in the Rc, i', and K bands with indices of -0.71+/-0.10, -1.23+/-0.10, and -0.53+/-0.09. However, H-band data show a power index change; the PE varies with A_V_ steeply (index of -0.95+/-0.30) when A_V_<2.88+/-0.67mag, but softly (index of -0.25+/-0.06) for greater AV values. The soft decay of PE in high-AV regions is consistent with the radiative alignment torque model, suggesting that our data trace the magnetic field to A_V_~20mag. Furthermore, the breakpoint found in the H band is similar to that for A_V_, where we found the P_Rc_/P_H_ dispersion significantly decreased. Therefore, the flat PE-A_V_ in high-A_V_ regions implies that the power-index changes result from additional grain growth.2017ApJ...849..157Whttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/849/157CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/226 : Stellar polarization catalogs agglomeration (Heiles, 2000)II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)I/311 : Hipparcos, the New Reduction (van Leeuwen, 2007)VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)VI/139 : Herschel Observation Log (Herschel Science Centre, 2013)II/349 : The Pan-STARRS release 1 (PS1) Survey - DR1 (Chambers+, 2016)J/ApJ/665/369 : Photopolarimetry of Southern Coalsack stars (Andersson+, 2007)J/A+A/502/845 : Dust coagulation in molecular clouds (Ormel+, 2009)J/ApJ/741/21 : Polarization of stars in Taurus (Chapman+, 2011)J/A+A/569/L1 : Polarization hole in a starless core (Alves+, 2014)J/ApJ/793/126 : L204 - Cloud 3 polarimetry and photometry (Cashman+, 2014)J/ApJ/833/176 : The magnetic field of L1544. I. NIR data (Clemens+, 2016)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/849/157https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/849/157http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/849/157https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/849/157https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/849/157http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/849/157GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/849/157/table1 (Measured polarization properties of stars probing the IC5146 dark cloud complex)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/849/157/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/849/157/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/849/157/table1?GETtext/xml+votable180.050000true328.875347.477890.0055555555555555566/14029 14030 14031 14040 14042 14052 14053 140548.650015785639275e-20 1.7003137259100215e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/849/157?format=asciiOpticalInfrareddefaultJ/ApJ/849/157/table1Measured polarization properties of stars probing the IC5146 dark cloud complexrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[1/48741] Polarimetric Catalog Star Numbermeta.id;meta.mainintRAJ2000[325.7/328.9] Right Ascension (J2000)degpos.eq.ra;meta.mainindexedDEJ2000[46.5/48.5] Declination (J2000)degpos.eq.dec;meta.mainindexedQR[-2.6/4]? Normalized Stokes Q in Rc-band%phys.polarization.stokes;arith.ratiofloatnullablee_QR[0.02/0.8]? Uncertainty in QR%stat.errorfloatnullableUR[-3.3/6.3]? Normalized Stokes U in Rc-band%phys.polarization.stokes;arith.ratiofloatnullablee_UR[0.01/0.8]? Uncertainty in UR%stat.errorfloatnullablePR[0/6.4]? Debiased Rc-band polarization percentage%phys.polarization;em.opt.Rfloatnullablee_PR[0.03/0.8]? Uncertainty in PR%stat.errorfloatnullablePAR[0.6/180]? Rc-band Polarization Angledegpos.posAng;phys.polarizationfloatnullablee_PAR[0.3/75]? Uncertainty in PARdegstat.errorfloatnullableQi[-3.7/6]? Normalized Stokes Q in i'-band%phys.polarization.stokes;arith.ratiofloatnullablee_Qi[0.02/1]? Uncertainty in Qi%stat.errorfloatnullableUi[-2.4/6.6]? Normalized Stokes U in i'-band%phys.polarization.stokes;arith.ratiofloatnullablee_Ui[0.02/1]? Uncertainty in Ui%stat.errorfloatnullablePi[0.5/6.6]? Debiased i'-band polarization percentage%phys.polarization;em.opt.Ifloatnullablee_Pi[0.02/1]? Uncertainty in Pi%stat.errorfloatnullablePAi[0.5/180]? i'-band Polarization Angledegpos.posAng;phys.polarizationfloatnullablee_PAi[0.3/9.5]? Uncertainty in PAidegstat.errorfloatnullableQH[-99.9/99.9]? Normalized Stokes Q in H-band%phys.polarization.stokes;arith.ratiofloatnullablee_QH[0.08/99.9]? Uncertainty in QH%stat.errorfloatnullableUH[-99.9/99.9]? Normalized Stokes U in H-band%phys.polarization.stokes;arith.ratiofloatnullablee_UH[0.08/99.9]? Uncertainty in UH%stat.errorfloatnullablePH[0/99.9]? Debiased H-band polarization percentage%phys.polarizationfloatnullablee_PH[0.08/99]? Uncertainty in PH%stat.errorfloatnullablePAH[0/180]? H-band Polarization Angledegpos.posAng;phys.polarizationfloatnullablee_PAH[1.3/180]? Uncertainty in PAHdegstat.errorfloatnullableQK[-95.3/99.9]? Normalized Stokes Q in K-band%phys.polarization.stokes;arith.ratiofloatnullablee_QK[0.1/99.9]? Uncertainty in QK%stat.errorfloatnullableUK[-99.1/89.5]? Normalized Stokes U in K-band%phys.polarization.stokes;arith.ratiofloatnullablee_UK[0.1/99.9]? Uncertainty in UK%stat.errorfloatnullablePK[0/99.9]? Debiased K-band polarization percentage%phys.polarizationfloatnullablee_PK[0.1/99]? Uncertainty in PK%stat.errorfloatnullablePAK[0/180]? K-band Polarization Angledegpos.posAng;phys.polarizationfloatnullablee_PAK[2.8/180]? Uncertainty in PAKdegstat.errorfloatnullableJmag[5.5/17.6]? 2MASS J-band magnitudemagphot.mag;em.IR.Jdoublenullablee_Jmag[0.007/2.3]? Uncertainty in Jmagmagstat.error;phot.mag;em.IR.JdoublenullableHmag[4.4/16.5]? 2MASS H-band magnitudemagphot.mag;em.IR.Hdoublenullablee_Hmag[0.007/1]? Uncertainty in Hmagmagstat.error;phot.mag;em.IR.HdoublenullableKsmag[3.9/16.3]? 2MASS Ks-band magnitudemagphot.mag;em.IR.Kdoublenullablee_Ksmag[0.005/0.8]? Uncertainty in Kmagmagstat.error;phot.mag;em.IR.KdoublenullableW1mag[4/16.1]? WISE band 1 magnitudemagphot.mag;em.IR.3-4umdoublenullablee_W1mag[0.02/0.5]? Uncertainty in W1magmagstat.error;phot.magdoublenullableW2mag[4/17.7]? WISE band 2 magnitudemagphot.mag;em.IR.4-8umdoublenullablee_W2mag[0.01/0.6]? Uncertainty in W2magmagstat.error;phot.magdoublenullableAv[-3.7/28.8]? NICER extinction (1)magphys.absorptionfloatnullableUF[0/1] Usage Flag: 1=Selected for further analysis; 0=Not selectedmeta.codeintWISEADisplay the AllWISE data (II/328) within 2"meta.ref.urlcharSloanDisplay the online SDSS data for the nearest objectmeta.ref.urlchar2MDisplay the 2MASS data (Cutri+ 2003, II/246) within 2"meta.ref.urlchar