NGC 1980 Is Not a Foreground Population of Orion: Spectroscopic Survey of Young Stars with Low Extinction in Orion A
Kim, Jinyoung Serena
AffiliationUniv Arizona, Dept Astron
Univ Arizona, Dept Planetary Sci
Keywordsaccretion, accretion disks
stars: pre-main sequence Supporting material: machine-readable tables
MetadataShow full item record
PublisherIOP PUBLISHING LTD
CitationNGC 1980 Is Not a Foreground Population of Orion: Spectroscopic Survey of Young Stars with Low Extinction in Orion A 2017, 153 (4):188 The Astronomical Journal
JournalThe Astronomical Journal
Rights© 2017. The American Astronomical Society. All rights reserved.
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at email@example.com.
AbstractWe perform a spectroscopic survey of the foreground population in Orion. A with MMT/Hectospec. We use these data, along with archival spectroscopic data and photometric data, to derive spectral types, extinction values, and masses for 691 stars. Using the Spitzer Space Telescope data, we characterize the disk properties of these sources. We identify 37 new transition disk (TD) objects, 1 globally depleted disk candidate, and 7 probable young debris disks. We discover an object with a mass of. less than 0.018-0.030 M-circle dot, which harbors a flaring disk. Using the Ha emission line, we characterize the accretion activity of the sources with disks, and confirm that the. fraction of accreting TDs is lower than that of optically thick disks (46% +/- 7% versus 73% +/- 9%, respectively). Using kinematic data from the Sloan Digital Sky Survey and APOGEE INfrared Spectroscopy of the Young Nebulous Clusters program (IN-SYNC), we confirm that the foreground population shows similar kinematics to their local molecular clouds and other young stars in the same regions. Using the isochronal ages, we find that the foreground population has a median age of. around 1-2 Myr, which is similar to that of other young stars in Orion. A. Therefore, our results argue against the presence of a large and old foreground cluster in front of Orion. A.
VersionFinal published version
SponsorsNational Aeronautics and Space Administration [NNX15AD94G]; National Science Foundation of China (NSFC) [11303037, 11390371/2]; Chinese Academy of Sciences (CAS) through a CAS-CONICYT Postdoctoral Fellowship; National Astronomical Observatories of China; Chinese Academy of Sciences [XDB09000000]; Ministry of Finance