J/ApJ/908/49ivo://CDS.VizieR/J/ApJ/908/49doi:10.26093/cds/vizier.19080049CDSFang M.Kim J.S.Pascucci I.Apai D.2024-11-06T20:23:01Z2024-02-12T09:18:34ZCDS support team

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

cds-question@unistra.frpre-main-sequence-starsstellar-spectral-typesextinctionvisible-astronomyWe present a study of the Trapezium cluster in Orion. We analyze flux- calibrated Very Large Telescope/Multi-Unit Spectroscopic Explorer spectra of 361 stars to simultaneously measure the spectral types, reddening, and the optical veiling due to accretion. We find that the extinction law from Cardelli et al. with a total-to-selective extinction value of RV=5.5 is more suitable for this cluster. For 68% of the sample the new spectral types are consistent with literature spectral types within two subclasses but, as expected, we derive systematically later types than the literature by one to two subclasses for the sources with significant accretion levels. Here we present an improved Hertzsprung-Russell (H-R) diagram of the Trapezium cluster, in which the contamination by optical veiling on spectral types and stellar luminosities has been properly removed. A comparison of the locations of the stars in the H-R diagram with the non-magnetic and magnetic pre-main-sequence evolutionary tracks indicates an age of 1-2Myr. The magnetic pre-main-sequence evolutionary tracks can better explain the luminosities of the low-mass stars. In the H-R diagram, the cluster exhibits a large luminosity spread ({sigma}(LogL*/L{sun})~0.3). By collecting a sample of 14 clusters/groups with different ages, we find that the luminosity spread tends to be constant ({sigma}(LogL*/L{sun})~0.2-0.25) after 2Myr, which suggests that age spread is not the main cause of the luminosity spread. There are ~0.1dex larger luminosity spreads for the younger clusters, e.g., the Trapezium cluster, than the older clusters, which can be explained by the starspots, accretion history, and circumstellar disk orientations.2021ApJ...908...49Fhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/908/49CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/62 : Catalogue of Extinction Data (Neckel+, 1980)III/150 : Perkins Revised MK Types for the Cooler Stars (Keenan+ 1989)VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)J/AJ/113/1733 : Orion Nebula Cluster population (Hillenbrand 1997)J/A+AS/123/329 : New weak-line T Tauri stars in Lupus (Krautter+ 1997)J/A+A/326/211 : T Tau Stars (Wichmann+, 1997)J/AJ/116/1816 : JHKLMNOPQ photometry in Orion cluster (Hillenbrand+, 1998)J/A+A/333/619 : Upper Scorpius OB association Li survey (Preibisch+ 1998)J/ApJ/525/466 : Young low-mass stars & brown dwarfs in IC 348 (Luhman+, 1999)J/ApJ/540/236 : KH photometry of Orion Nebula Cluster (Hillenbrand+, 2000)J/ApJ/540/1016 : K-band & NICMOS photometry Trapezium Cluster (Luhman+, 2000)J/A+A/396/513 : Stellar Rotation in the Orion Nebula Cluster (Herbst+, 2002)J/AJ/124/1670 : Post-T Tauri Stars in Sco-Cen Association (Mamajek+, 2002)J/ApJ/573/366 : Infrared photometry of Trapezium cluster (Muench+, 2002)J/ApJ/593/1093 : IC 348 membership (Luhman+, 2003)J/ApJ/601/979 : vsini of Orion low-mass stars (Wolff+, 2004)J/other/ARA+A/42.685 : Young stars near the Sun (Zuckerman+, 2004)J/AJ/130/1805 : H{alpha} emission stars in NGC 2362 (Dahm+, 2005)J/AJ/129/1534 : Mid-IR photometry in the Orion Nebula (Robberto+, 2005)J/AJ/130/1763 : 11.7{mu}m point sources in Orion (Smith+, 2005)J/ApJ/645/676 : Spatial distribution brown dwarfs in Taurus (Luhman+, 2006)J/AJ/132/866 : New M dwarfs in solar neighborhood (Riaz+, 2006)J/A+A/460/695 : Search Associations Containing Young stars (Torres+, 2006)J/MNRAS/376/580 : Cousins RI photometry of NGC 2169 (Jeffries+, 2007)J/ApJS/173/104 : Stellar population in Chamaeleon I (Luhman, 2007)J/AJ/136/1290 : Ultracool dwarfs from the 2MASS (Reid+, 2008)J/AJ/136/2136 : HST/ACS Atlas of Great Orion Nebula proplyds (Ricci+, 2008)J/A+A/488/167 : Low-mass stars in {sigma} Ori and {lambda} Ori (Sacco+, 2008)J/A+A/504/461 : YSOs in L1630N and L1641 (Fang+, 2009)J/ApJ/722/1092 : Optical photometry of the ONC. II. (Da Rio+, 2010)J/A+A/521/A18 : Blue stars with disk photometry in NGC6611 (Guarcello+, 2010)J/AJ/139/950 : JHKs photometry in ONC (Robberto+, 2010)J/ApJ/724/835 : The Spitzer c2d survey of WTTSs. III. (Wahhaj+, 2010)J/ApJ/731/8 : Multiple star formation in Taurus-Auriga (Kraus+, 2011)J/ApJ/748/14 : ONC population data from WFI observations (Da Rio+, 2012)J/AJ/144/192 : Spitzer survey of Orion A & B. I. YSO cat. (Megeath+, 2012)J/ApJ/745/119 : Close companions to young stars I. ChaI & Tau (Nguyen+, 2012)J/A+A/548/A56 : X-shooter spectra 12 young stellar objects (Rigliaco+, 2012)J/ApJS/207/5 : YSOs in LDN 1641 with Hectochelle spectra (Fang+, 2013)J/AJ/146/85 : Spectral types 1576 optical stars in ONC (Hillenbrand+, 2013)J/A+A/551/A107 : X-shooter spectra of 24 young stellar objects (Manara+, 2013)J/ApJS/208/9 : Intrinsic colors & temperatures of PMS stars (Pecaut+, 2013)J/A+A/561/A2 : 36 accreting YSOs emission lines (Alcala+, 2014)J/ApJ/786/97 : Photospheric properties of T Tauri stars (Herczeg+, 2014)J/ApJ/794/36 : {sigma} Orionis cluster stellar population (Hernandez+, 2014)J/A+A/593/A7 : NH and AV Towards YSOs in the ONC (Hasenberger+, 2016)J/ApJ/831/125 : ALMA 887um obs. of ChaI star-forming region (Pascucci+, 2016)J/MNRAS/461/794 : Scorpius-Centaurus K-Type Stars (Pecaut+, 2016)J/A+A/600/A20 : Lupus YSOs X-shooter spectroscopy (Alcala+, 2017)J/AJ/153/188 : Spectroscopy of foreground population in OrionA (Fang+, 2017)J/ApJ/834/142 : Gould's Belt Distances Survey. II. OMC (Kounkel+, 2017)J/ApJ/838/150 : The Taurus-Auriga ecosystem. I. (Kraus+, 2017)J/AJ/153/46 : Spectroscopy of candidate members in Taurus (Luhman+, 2017)J/A+A/605/A86 : Pre-main sequence stars VLT/X-Shooter spectra (Manara+, 2017)J/AJ/156/84 : APOGEE-2 survey of Orion Complex. II. (Kounkel+, 2018)J/AJ/156/76 : New young stars and brown dwarfs in Upper Sco (Luhman+, 2018)J/A+A/609/A10 : NGC2264 structure and star formation history (Venuti+, 2018)J/AJ/157/85 : The CIDA Variability Survey of Orion OB1 II. (Briceno+, 2019)J/A+A/632/A46 : TW Hydrae association with X-shooter (Venuti+, 2019)J/ApJ/904/146 : Young stars North the America & Pelican Nebulae (Fang+, 2020)J/ApJ/893/67 : Smoothed amplitudes from Kepler K2 & TESS phot (Morris, 2020)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/908/49https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/908/49http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/908/49https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/908/49https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/908/49http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/908/49GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/908/49/table1 (List of sources, their Spectral types and stellar luminosities)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/908/49/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/908/49/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/908/49/table1?GETtext/xml+votable180.050000true83.772375-5.40294440.0055555555555555566/21439https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/908/49?format=asciiOpticaldefaultJ/ApJ/908/49/table1List of sources, their Spectral types and stellar luminositiesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintID[1/361] Internal identifiermeta.id;meta.mainintRAJ2000[5/5] Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000[5/5] Degree of Declination (J2000)pos.eq.dec;meta.mainSpT1Spectral type from method 1 (1)src.spTypecharlogL*-1[-2.15/1.68] log stellar luminosity from method 1 (1)solLumphys.luminosityfloatAV-1[0/6.37] V band extinction from method 1 (1)magphys.absorption;em.opt.Vfloatr7465-1[0/4.8] Veiling at 7465A from method 1 (1)phys.absorption;em.opt.VfloatSpT-2Spectral type from method 2 (2)src.spTypecharlogL*-2[-2.01/1.68] log stellar luminosity from method 2 (2)solLumphys.luminosityfloatAV-2[0/6.58] V band extinction from method 2 (2)magphys.absorption;em.opt.Vfloatr7465-2[0/4.44] Veiling at 7465A from method 2 (2)phys.absorption;em.opt.VfloatSpT-3Spectral type from method 3 (3)src.spTypecharlogL*-3[-2.07/1.79] log stellar luminosity from method 3 (3)solLumphys.luminosityfloatAV-3[0/7.79] V band extinction from method 3 (3)magphys.absorption;em.opt.Vfloatr7465-3[0/4.78] Veiling at 7465A from method 3 (3)phys.absorption;em.opt.VfloatSpT-4Spectral type from method 4 (4)src.spTypecharlogL*-4log[-1.97/1.79] stellar luminosity from method 4 (4)solLumphys.luminosityfloatAV-4[0/7.85] V band extinction from method 4 (4)magphys.absorption;em.opt.Vfloatr7465-4[0/4.43] Veiling at 7465A from method 4 (4)phys.absorption;em.opt.VfloatStar[265/9320]? Hillenbrand+, 2013, J/AJ/146/85 identifiermeta.idintnullableSpTLiterature spectral type (5)src.spTypechar