Spectroscopic confirmation of M-dwarf candidate members of the Beta Pictoris and AB Doradus Moving Groups

Abstract

Optical spectroscopic observations are reported for 24 and 23, nearby, proper-motion-selected M-dwarf candidate members of the Beta Pictoris and AB Doradus moving groups (BPMG and ABDMG). Using kinematic criteria, the presence of both Halpha emission and high X-ray-to-bolometric luminosity, and position in absolute colour-magnitude diagrams, 10 and 6 of these candidates are confirmed as likely members of the BPMG and ABDMG respectively. Equivalent widths or upper limits for the Li I 6708A line are reported and the lithium depletion boundary (LDB) age of the BPMG is revisited. Whilst non-magnetic evolutionary models still yield an estimated age of 21 +/- 4 Myr, models that incorporate magnetic inhibition of convection imply an older age of 24 +/- 4 Myr. A similar systematic increase would be inferred if the stars were 25 per cent covered by dark magnetic starspots. Since young, convective M-dwarfs are magnetically active and do have starspots, we suggest that the original LDB age estimate is a lower limit. The LDB age of the ABDMG is still poorly constrained -- non-magnetic evolutionary models suggest an age in the range 35-150 Myr, which could be significantly tightened by new measurements for existing candidate members.

Accepted for publication in MNRAS (revised version corrects erroneous Table 2)

References in corpus (25)

• The Dartmouth Stellar Evolution Database
• New evolutionary models for pre-main sequence and main sequence low-mass stars down to the hydrogen-burning limit
• Discovery and spectroscopy of the young Jovian planet 51 Eri b with the Gemini Planet Imager
• A self-consistent, absolute isochronal age scale for young moving groups in the solar neighbourhood
• On the age of the $\beta$ Pictoris moving group
• The Radial Velocity Experiment (RAVE): second data release
• Planets Around Low-Mass Stars (PALMS). IV. The Outer Architecture of M Dwarf Planetary Systems
• A Stellar Census of the Tucana-Horologium Moving Group
• The Factory and The Beehive II. Activity and Rotation in Praesepe and the Hyades
• BANYAN. IV. Fundamental parameters of low-mass star candidates in nearby young stellar kinematic groups - Isochronal Age determination using Magnetic evolutionary models
• Young Nearby Loose Associations
• Older and Colder: The impact of starspots on pre-main sequence stellar evolution
• BANYAN. V. A Systematic All-Sky Survey for New Very Late-Type Low-Mass Stars and Brown Dwarfs in Nearby Young Moving Groups
• SDSS J111010.01+011613.1: A New Planetary-Mass T Dwarf Member of the AB Doradus Moving Group
• Search for associations containing young stars (SACY). V. Is multiplicity universal? Tight multiple systems
• On the AU Mic debris disk: density profiles, grain properties and dust dynamics
• On the common origin of the AB Dor moving group and the Pleiades cluster
• Reaching the boundary between stellar kinematic groups and very wide binaries. III. Sixteen new stars and eight new wide systems in the beta Pictoris moving group
• Pre-main-sequence isochrones -- III. The Cluster Collaboration isochrone server
• Using rotation, magnetic activity and lithium to estimate the ages of low mass stars
• The effect of starspots on the ages of low-mass stars determined from the lithium depletion boundary
• The Near-Ultraviolet Luminosity Function of Young, Early M-Type Dwarf Stars
• Planets Around Low-Mass Stars (PALMS). V. Age-Dating Low-Mass Companions to Members and Interlopers of Young Moving Groups
• Cumulative theoretical uncertainties in lithium depletion boundary age
• Characterizing the AB Doradus Moving Group Via High Resolution Spectroscopy and Kinematic Traceback

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• Magnetic Inhibition of Convection and the Fundamental Properties of Low-Mass Stars. III. A Consistent 10 Myr Age for the Upper Scorpius OB Association
• CARMENES input catalogue of M dwarfs V. Luminosities, colours, and spectral energy distributions
• Dynamical traceback age of the $\beta$ Pictoris moving group
• Refining the Census of the Upper Scorpius Association with Gaia
• All-sky Co-moving Recovery Of Nearby Young Members. (ACRONYM) II: The Beta Pictoris Moving Group
• The Orbit and Transit Prospects for $\beta$ Pictoris b constrained with One Milliarcsecond Astrometry
• The Greater Taurus-Auriga Ecosystem I: There Is A Distributed Older Population
• The Gaia-ESO Survey: Lithium depletion in the Gamma Velorum cluster and inflated radii in low-mass pre-main-sequence stars
• A Census of the Stellar Populations in the Sco-Cen Complex
• HAZMAT III: The UV Evolution of Mid- to Late-M Stars with GALEX
• A Census of the Taurus Star-forming Region and Neighboring Associations with Gaia
• ACRONYM III: Radial Velocities for 336 Candidate Young Low-Mass Stars in the Solar Neighborhood, Including 78 Newly Confirmed Young Moving Group Members
• Search for associations containing young stars (SACY) VII. New stellar and substellar candidate members in the young associations
• A detailed characterization of HR 8799's debris disk with ALMA in Band 7
• WISE J080822.18-644357.3 - a 45 Myr-old accreting M dwarf hosting a primordial disc
• The Elusive Majority of Young Moving Groups. I. Young Binaries and Lithium-Rich Stars in the Solar Neighborhood
• JWST/NIRSpec Observations of the Planetary Mass Companion TWA 27B
• A Census of the TW Hya Association with Gaia
• The beta Pictoris association: Catalog of photometric rotational periods of low-mass members and candidate members
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• A stellar census of the nearby, young 32 Orionis group
• Searching for flaring star-planet interactions in AU Mic TESS observations
• Addressing Systematics in the Traceback Age of the $\beta$ Pictoris Moving Group
• A WISE-based search for debris discs amongst M-dwarfs in nearby, young, moving groups
• A Comprehensive Dust Model Applied to the Resolved Beta Pictoris Debris Disk from Optical to Radio Wavelengths
• The Atacama Cosmology Telescope: Detection of mm-wave transient sources
• The Gaia-ESO survey: A lithium depletion boundary age for NGC 2232
• Bayesian assessment of moving group membership: importance of models and prior knowledge
• A Census of the 32 Ori Association with Gaia
• The $\beta$ Pictoris b Hill sphere transit campaign. Paper I: Photometric limits to dust and rings
• bRing: An observatory dedicated to monitoring the $\beta$ Pictoris b Hill sphere transit
• Non-thermal radio continuum emission from young nearby stars
• Searching for new young stars in the northern hemisphere: The Pisces Moving Group
• Disks in Nearby Young Stellar Associations Found Via Virtual Reality
• COol Companions ON Ultrawide orbiTS (COCONUTS). III. A Very Red L6 Benchmark Brown Dwarf around a Young M5 Dwarf
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• The Gaia Ultracool Dwarf Sample -- IV. GTC/OSIRIS optical spectra of Gaia late-M and L dwarfs
• Nearby Young Stars and Young Moving Groups
• Stellar-activity analysis of the nearby M dwarf GJ 526. Multi-dimensional Gaussian-process modelling of RV, FWHM and S-index
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