TY - JOUR
T1 - Investigating 2M1155−79B
T2 - A Nearby, Young, Low-mass Star Actively Accreting from a Nearly Edge-on, Dusty Disk
AU - Dickson-Vandervelde, D. Annie
AU - Kastner, Joel H.
AU - Gagné, Jonathan
AU - Schneider, Adam C.
AU - Faherty, Jacqueline
AU - Wilson, Emily C.
AU - Pinte, Christophe
AU - Ménard, Francois
N1 - Funding Information:
We thank the anonymous referee for helpful comments and suggestions. This research is supported by NASA Exoplanets Program grant 80NSSC19K0292 to Rochester Institute of Technology. This work has made use of data from the European Space Agency (ESA) mission Gaia ( https://www.cosmos.esa.int/gaia ), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium ). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. This publication makes use of data products from the Two Micron All Sky Survey, which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation. This publication makes use of data products from the Wide-field Infrared Survey Explorer, which is a joint project of the University of California, Los Angeles, and the Jet Propulsion Laboratory/California Institute of Technology, funded by the National Aeronautics and Space Administration.
Funding Information:
We thank the anonymous referee for helpful comments and suggestions. This research is supported by NASA Exoplanets Program grant 80NSSC19K0292 to Rochester Institute of Technology. This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. This publication makes use of data products from the Two Micron All Sky Survey, which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation. This publication makes use of data products from the Wide-field Infrared Survey Explorer, which is a joint project of the University of California, Los Angeles, and the Jet Propulsion Laboratory/California Institute of Technology, funded by the National Aeronautics and Space Administration.
Publisher Copyright:
© 2022. The Author(s). Published by the American Astronomical Society.
PY - 2022/11/1
Y1 - 2022/11/1
N2 - We investigate the nature of an unusually faint member of the ϵ Cha association (D ∼ 100 pc, age ∼5 Myr), the nearest region of star formation of age <8 Myr. This object, 2MASS J11550336−7919147 (2M1155−79B), is a wide-separation (∼580 au), comoving companion to low-mass (M3) ϵ Cha association member 2MASS J11550485−7919108 (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 He i 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 ≲ 100 pc), young (age <10 Myr) 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.
AB - We investigate the nature of an unusually faint member of the ϵ Cha association (D ∼ 100 pc, age ∼5 Myr), the nearest region of star formation of age <8 Myr. This object, 2MASS J11550336−7919147 (2M1155−79B), is a wide-separation (∼580 au), comoving companion to low-mass (M3) ϵ Cha association member 2MASS J11550485−7919108 (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 He i 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 ≲ 100 pc), young (age <10 Myr) 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.
UR - http://www.scopus.com/inward/record.url?scp=85141755953&partnerID=8YFLogxK
U2 - 10.3847/1538-3881/ac9674
DO - 10.3847/1538-3881/ac9674
M3 - Article
AN - SCOPUS:85141755953
SN - 0004-6256
VL - 164
JO - The Astronomical Journal
JF - The Astronomical Journal
IS - 5
M1 - 227
ER -