The Late-Type Extension to MoVeRS (LaTE-MoVeRS): Proper motion verified low-mass stars and brown dwarfs from SDSS, 2MASS, and WISE

TL;DR

The LaTE-MoVeRS catalog extends the identification of low-mass stars and brown dwarfs using proper motion data from SDSS, 2MASS, and WISE, revealing new nearby objects and providing insights into their properties.

Contribution

This work introduces the LaTE-MoVeRS catalog, combining multi-epoch data to verify low-mass stars and brown dwarfs, and estimates their distances and temperatures, enhancing the census of nearby late-type objects.

Findings

Identified 13 new objects within 25 pc of Earth.

Discovered a new L2γ dwarf with infrared excess and flaring signs.

Estimated Gaia will be ~64% complete for late-type low-mass stars.

Abstract

We present the Late-Type Extension to the Motion Verified Red Stars (LaTE-MoVeRS) catalog, containing 46,463 photometric late-type ($>$ M5) dwarfs within the Sloan Digital Sky Survey (SDSS) footprint. Proper motions were computed for objects combining astrometry from the SDSS Data Release 12 (DR12), the Two-Micron All-Sky Survey (2MASS) Point Source Catalog (PSC), and the \emph{Wide-field Infrared Survey Explorer} (\emph{WISE}) AllWISE datasets. LaTE-MoVeRS objects were required to have significant proper motion ($\mu_\mathrm{tot} \geqslant 2\sigma_{\mu_\mathrm{tot}}$). Using the LaTE-MoVeRS sample and \emph{Gaia} Data Release 1, we estimate \emph{Gaia} will be $\sim$64\% complete for very-low-mass objects ($>$ M5) in comparison to the combined SDSS+2MASS+\emph{WISE} dataset ($i < 21.3$). We computed photometric distances and estimated stellar effective temperatures for the LaTE-MoVeRS catalog. The majority of the dwarfs in the sample have distances $< 150$ pc and $T_\mathrm{eff} < 3000$ K. Thirteen objects were identified within LaTE-MoVeRS with estimated photometric distances within 25 pc that have not been previously identified as nearby objects. We also identified one new object with a large amount of excess mid-infrared flux that has not been previously identified (2MASS J11151597$+$1937266). This object appears to be an L2$\gamma$ at $\sim$50 pc showing spectroscopic signs of a flaring event (e.g., strong Hydrogen Balmer emission lines). This object does not exhibit kinematics similar to any known kinematic association. The LaTE-MoVeRS catalog is available through SDSS CasJobs and VizieR.