J/AJ/164/227ivo://CDS.VizieR/J/AJ/164/227doi:10.26093/cds/vizier.51640227CDSDickson-Vandervelde D.A.Kastner J.H.Gagne J.Schneider A.C.,Faherty J.Wilson E.C.Pinte C.Menard F.2023-01-18T06:22:38Z2022-12-23T08:19:56ZCDS support team

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

cds-question@unistra.frexoplanetspre-main-sequence-starsinfrared-astronomyspectroscopyWe investigate the nature of an unusually faint member of the {epsilon}Cha association (D~100pc, age ~5Myr), the nearest region of star formation of age <8Myr. This object, 2MASSJ11550336-7919147 (2M1155-79B), is a wide-separation (~580au), comoving companion to low-mass (M3) {epsilon}Cha association member 2MASSJ11550485-7919108 (2M1155-79A). We present near-infrared (NIR) spectra of both components, along with analysis of photometry from Gaia Early Data Release 3, the Two Micron All Sky Survey, the Vista Hemisphere Survey, and the Wide-field Infrared Survey Explorer (WISE). The NIR spectrum of 2M1155-79B displays strong HeI 1.083 emission, a sign of active accretion and/or accretion-driven winds from a circumstellar disk. Analysis of WISE archival data reveals that the mid-infrared excess previously associated with 2M1155-79A instead originates from the disk surrounding 2M1155-79B. Based on these results, as well as radiative transfer modeling of its optical/IR spectral energy distribution, we conclude that 2M1155-79B is most likely a young, late M star that is partially obscured by, and actively accreting from, a nearly edge-on circumstellar disk. This would place 2M1155-79B among the rare group of nearby (D<~100pc), young (age <10Myr) mid-M stars that are orbited by and accreting from highly inclined protoplanetary disks. Like these systems, the 2M1155-79B system is a particularly promising subject for studies of star and planet formation around low-mass stars.2022AJ....164..227Dhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/164/227CatalogResearchIsServedByTAP VizieR generic servicerelated-toII/359 : The VISTA Hemisphere Survey (VHS) catalog DR4.1 (McMahon+, 2013)I/337 : Gaia DR1 (Gaia Collaboration, 2016)II/363 : The band-merged unWISE Catalog (Schlafly+, 2019)I/352 : Distances to 1.47 billion stars in Gaia EDR3 (Bailer-Jones+, 2021)VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)J/MNRAS/435/1325 : Membership of the {epsilon} Cha association (Murphy+, 2013)J/ApJS/208/9 : Intrinsic colors and temperatures of PMS stars (Pecaut+, 2013)J/AJ/153/46 : Spectroscopy of candidate members in Taurus (Luhman+, 2017)J/ApJ/862/138 : BANYAN. XIII. Nearby young assoc. with Gaia DR2 (Gagne+, 2018)J/A+A/625/A135 : Galactic interstellar dust Gaia2MASS 3Dmaps (Lallement+, 2019)J/AJ/160/44 : Upper Scorpius spectroscopy and photometry (Luhman+, 2020)J/MNRAS/502/6117 : A faint companion around CrA-9 (Christiaens+, 2021)J/AJ/161/87 : Gaia data members of {epsilon}Cha (Dickson-Vandervelde+, 2021)J/MNRAS/503/2265 : VISTA and Subaru/HSC obs. of Upper Scorpius (Lodieu+, 2021)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/164/227https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/164/227http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/164/227https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/164/227https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/164/227http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/164/227GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapInfrareddefaultJ/AJ/164/227/fig1Near-IR spectra obtained with the FIRE instrument on Magellan for 2M1155-79A and 2M1155-79BDateObservation date code (1)meta.code;time.epochintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDObject identifiermeta.id;meta.maincharWave[0/3] Wavelengthumem.wlfloatFlux[-4e-14/2] Flux density; erg/s/cm^2^/AcW.m**-2.nm**-1phot.flux.density;em.IR.NIRdoublee_Flux[0/19]Uncertainty in Flux; erg/s/cm^2^/AcW.m**-2.nm**-1stat.error;phot.fluxdouble