Spectroscopy and kinematics of low-mass members of young moving groups

Abstract

We study a target sample of 68 low-mass objects (with spectral types in the range M4.5-L1) previously selected via photometric and astrometric criteria, as possible members of five young moving groups: the Local Association (Pleiades moving group, age=20 - 150 Myr), the Ursa Mayor group (Sirius supercluster, age=300 Myr), the Hyades supercluster (age=600 Myr), IC 2391 supercluster (age=35 - 55 Myr) and the Castor moving group (age=200 Myr). In this paper we assess their membership by using different kinematic and spectroscopic criteria. We use high resolution echelle spectroscopic observations of the sample to measure accurate radial velocities (RVs). Distances are calculated and compared to those of the moving group from the literature, we also calculate the kinematic Galactic components (U,V,W) of the candidate members and apply kinematic criterion of membership to each group. In addition we measure rotational velocities (v sin i) to place further constraints on membership of kinematic members. We find that 49 targets have young disk kinematics and that 36 of them possibly belong to one of our five moving groups. From the young disk target ob jects, 31 have rotational velocities in agreement with them belonging to the young disk population. We also find that one of our moving group candidates, 2MASS0123- 3610, is a low-mass double lined spectroscopic binary, with probable spectral types around M7.

16 pg, 5 figures

References in corpus (21)

• Constraining the Age-Activity Relation for Cool Stars: The SDSS DR5 Low-Mass Star Spectroscopic Sample
• Chromospheric Activity, Rotation, and Rotational Braking in M and L Dwarfs
• Rotation Velocities for M-dwarfs
• A search for binary systems among the nearest L dwarfs
• The Wide Brown Dwarf Binary Oph 1622-2405 and Discovery of A Wide, Low Mass Binary in Ophiuchus (Oph 1623-2402): A New Class of Young Evaporating Wide Binaries?
• A Survey for Spectroscopic Binaries Among Very Low-Mass Stars
• Origin and evolution of moving groups I. Characterization in the observational kinematic-age-metallicity space
• Finding benchmark brown dwarfs to probe the IMF as a function of time
• The Hyades stream: evaporated cluster or intrusion from the inner disk?
• Brown dwarfs and very low mass stars in the Hyades cluster : a dynamically evolved mass function
• A Volume-limited Sample of 63 M7--M9.5 Dwarfs I. Space Motion, Kinematic Age, and Lithium
• On the age heterogeneity of the Pleiades, Hyades and Sirius moving groups
• Keck Laser Guide Star Adaptive Optics Monitoring of the M8+L7 Binary LHS 2397aAB: First Dynamical Mass Benchmark at the L/T Transition
• A multiwavelength radial velocity search for planets around the brown dwarf LP 944-20
• A Catalog of Moving Group Candidates in The Solar Neighborhood
• Reaching the boundary between stellar kinematic groups and very wide binaries. II. alpha Lib + KU Lib: a common proper motion system in Castor separated by 1.0 pc
• On the kinematic age of brown dwarfs: Radial velocities and space motions of 43 nearby L dwarfs
• Formation of giant planets around stars with various masses
• L dwarfs in the Hyades
• Spectral analysis of high resolution near-infrared spectra of ultra cool dwarfs
• NACO-SDI imaging of known companion host stars from the AAPS and Keck planet search surveys

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• BANYAN. II. Very Low Mass and Substellar Candidate Members to Nearby, Young Kinematic Groups With Previously Known Signs of Youth
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• BANYAN. VII. A New Population of Young Substellar Candidate Members of Nearby Moving Groups from the BASS Survey
• BANYAN. III. Radial velocity, Rotation and X-ray emission of low-mass star candidates in nearby young kinematic groups
• BANYAN. V. A Systematic All-Sky Survey for New Very Late-Type Low-Mass Stars and Brown Dwarfs in Nearby Young Moving Groups
• A large spectroscopic sample of L and T dwarfs from UKIDSS LAS: peculiar objects, binaries, and space density
• Dynamical Analysis of Nearby ClustErs. Automated astrometry from the ground: precision proper motions over wide field
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• The Ultracool SpeXtroscopic Survey. I. Volume-Limited Spectroscopic Sample and Luminosity Function of M7$-$L5 Ultracool Dwarfs
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• Towards a complete stellar mass function of the Hyades. I. Pan-STARRS1 optical observations of the low-mass stellar content
• Stellar activity as a tracer of moving groups
• Parallaxes of southern extremely cool objects III: 118 L \& T dwarfs
• Spectroscopic signatures of youth in low-mass kinematic candidates of young moving groups
• Detection of lithium in nearby young late-M dwarfs
• Projected Rotational Velocities and Fundamental Properties of Low-Mass Pre-Main Sequence Stars in the Taurus-Auriga Star Forming Region
• The Fundamental Stellar Parameters of FGK Stars in the SEEDS Survey
• Kinematic identification of young nearby moving groups from a sample of chromospherically active stars in the RAVE catalog