Physical properties and trigonometric distance of the peculiar dwarf WISE J181005.5$-$101002.3

Abstract

Our goal is to characterise the physical properties of the metal-poor brown dwarf population. In particular, we focus on the recently discovered peculiar dwarf WISE J1810055$-$1010023. We collected optical iz and near-infrared J-band imaging on multiple occasions over 1.5 years to derive accurate trigonometric parallax and proper motion of the metal-depleted ultra-cool dwarf candidate WISE1810. We also acquired low-resolution optical spectroscopy (0.6$-$1.0 $\mu$m) and new infrared (0.9$-$1.3 $\mu$m) spectra of WISE1810 that were combined with our photometry, other existing data from the literature and our trigonometric distance to determine the object's luminosity from the integration of the observed spectral energy distribution covering from 0.6 through 16$\mu$m. We compared the full optical and infrared spectrum with state-of-the-art atmosphere models to further constrain its effective temperature, surface gravity and metallicity. WISE1810 is detected in the $iz$ bands with AB magnitudes of $i$=23.871$\pm$0.104 and $z$=20.147$\pm$0.083 mag in the PanSTARRS system. It does not show any obvious photometric variability beyond 0.1$-$0.2 mag in any of the $z$- and $J$-band filters. The very red $z-J\approx 2.9$ mag colour is compatible with an ultra-cool dwarf nature. Fitting for parallax and proper motion, we measure a trigonometric parallax of 112.5${}_{-8.0}^{+8.1}$ mas for WISE1810, placing the object at only 8.9${}_{-0.6}^{+0.7}$ pc, about three times closer than previously thought. We employed Monte Carlo methods to estimate the error on the parallax and proper motion. The object's luminosity was determined at log$L/L_{\odot }$=$-$5.78$\pm$0.11 dex. From the comparison to atmospheric models, we infer a likely metallicity of [Fe/H] $\approx -1.5$ and an effective temperature cooler than 1000K. Abridged

arXiv comment12 pages, 15 figures, 6 tables, accepted for publications to A&A

References in corpus (82)

• The Wide-field Infrared Survey Explorer (WISE): Mission Description and Initial On-orbit Performance
• The UKIRT Infrared Deep Sky Survey (UKIDSS)
• The Milky Way Tomography with SDSS: I. Stellar Number Density Distribution
• Elemental Abundance Survey of The Galactic Thick Disk
• The UKIRT Infrared Deep Sky Survey ZYJHK Photometric System: Passbands and Synthetic Colours
• The Hawaii Infrared Parallax Program. I. Ultracool Binaries and the L/T Transition
• The UKIDSS Galactic Plane Survey
• The Solar Neighborhood XVII: Parallax Results from the CTIOPI 0.9m Program -- Twenty New Members of the RECONS 10 Parsec Sample
• A Unified Near Infrared Spectral Classification Scheme for T Dwarfs
• The WFCAM Science Archive
• Preliminary Parallaxes of 40 L and T Dwarfs from the U.S. Naval Observatory Infrared Astrometry Program
• The Spectra of T Dwarfs I: Near-Infrared Data and Spectral Classification
• The UKIRT Wide Field Camera ZYJHK Photometric System: Calibration from 2MASS
• The First Hundred Brown Dwarfs Discovered by the Wide-field Infrared Survey Explorer (WISE)
• VVV DR1: The First Data Release of the Milky Way Bulge and Southern Plane from the Near-Infrared ESO Public Survey VISTA Variables in the Via Lactea
• The Discovery of Y Dwarfs Using Data from the Wide-field Infrared Survey Explorer (WISE)
• Further Defining Spectral Type "Y" and Exploring the Low-mass End of the Field Brown Dwarf Mass Function
• M-Subdwarfs: Spectroscopic Classification and the Metallicity Scale
• The Brown Dwarf Kinematics Project (BDKP). III. Parallaxes for 70 Ultracool Dwarfs
• Discovery of a Brown Dwarf Companion to Gliese 570ABC: A 2MASS T Dwarf Significantly Cooler than Gliese 229B
• Distances, Luminosities, and Temperatures of the Coldest Known Substellar Objects
• Revised metallicity classes for low-mass stars: dwarfs (dM), subdwarfs (sdM), extreme subdwarfs (esdM), and ultra subdwarfs (usdM)
• The First Substellar Subdwarf? Discovery of a Metal-poor L Dwarf with Halo Kinematics
• Discovery of a ~250 K Brown Dwarf at 2 pc from the Sun
• CARMENES input catalogue of M dwarfs. I. Low-resolution spectroscopy with CAFOS
• Discovery of a Binary Brown Dwarf at 2 Parsecs from the Sun
• Spectroscopy of New High Proper Motion Stars in the Northern Sky. I. New Nearby Stars, New High Velocity Stars, and an Enhanced Classification Scheme for M Dwarfs
• The Spectra of T Dwarfs. II. Red Optical Data
• The Field Substellar Mass Function Based on the Full-sky 20-pc Census of 525 L, T, and Y Dwarfs
• Discovery of 11 New T Dwarfs in the Two Micron All-Sky Survey, Including a Possible L/T Transition Binary
• The AllWISE Motion Survey and The Quest for Cold Subdwarfs
• The 10 parsec sample in the Gaia era
• A Study of the Diverse T Dwarf Population Revealed by WISE
• Preliminary Trigonometric Parallaxes of 184 Late-T and Y Dwarfs and an Analysis of the Field Substellar Mass Function into the "Planetary" Mass Regime
• The CatWISE Preliminary Catalog: Motions from $WISE$ and $NEOWISE$ Data
• The 2MASS Wide-Field T Dwarf Search. IV Unting out T dwarfs with Methane Imaging
• Spectroscopic rotational velocities of brown dwarfs
• The Solar Neighborhood XLIV: RECONS Discoveries within 10 Parsecs
• The CARMENES search for exoplanets around M dwarfs. Stellar atmospheric parameters of target stars with SteParSyn
• The CARMENES search for exoplanets around M dwarfs - Photospheric parameters of target stars from high-resolution spectroscopy
• The Luminosity and Mass Functions of Low-Mass Stars in the Galactic Disk: I. The Calibration Region
• The lithium depletion boundary and the age of the Hyades cluster
• HiPERCAM: a quintuple-beam, high-speed optical imager on the 10.4-m Gran Telescopio Canarias
• The First Ultra-Cool Brown Dwarf Discovered by the Wide-field Infrared Survey Explorer
• The Y-Type Brown Dwarfs: Estimates of Mass and Age from New Astrometry, Homogenized Photometry and Near-Infrared Spectroscopy
• Discovery of the benchmark metal poor T8 dwarf BD+01 2920B
• What is limiting near-infrared astrometry in the Galactic Center?
• Primeval very low-mass stars and brown dwarfs. I. Six new L subdwarfs, classification and atmospheric properties
• ULAS J141623.94$+$134836.3 - a faint common proper motion companion of a nearby L dwarf. Serendipitous discovery of a cool brown dwarf in UKIDSS DR6
• The Luminosities of the Coldest Brown Dwarfs
• The Properties of the 500 K Dwarf UGPS J072227.51-054031.2, and a Study of the Far-Red Flux of Cold Brown Dwarfs
• New ultra-cool and brown dwarf candidates in Gaia DR2
• SDSS J141624.08+134826.7: A Nearby Blue L Dwarf From the Sloan Digital Sky Survey
• Signatures of Cloud, Temperature, and Gravity From Spectra of the Closest Brown Dwarfs
• The kinematics of late type stars in the solar cylinder studied with SDSS data
• A 3D view of the Hyades stellar and sub-stellar population
• Discovery of An Unusually Blue L Dwarf Within 10 pc of the Sun
• Spitzer Follow-up of Extremely Cold Brown Dwarfs Discovered by the Backyard Worlds: Planet 9 Citizen Science Project
• Expanding the Y Dwarf Census with Spitzer Follow-up of the Coldest CatWISE Solar Neighborhood Discoveries
• Blue not brown: UKIDSS T dwarfs with suppressed K-band flux
• A high resolution spectroscopic atlas of M subdwarfs - Effective temperature and metallicity
• Photometric brown-dwarf classification. I. A method to identify and accurately classify large samples of brown dwarfs without spectroscopy
• WISEA J041451.67-585456.7 and WISEA J181006.18-101000.5: The First Extreme T-type Subdwarfs?
• The Subdwarf Luminosity Function
• Primeval very low-mass stars and brown dwarfs - II. The most metal-poor substellar object
• Primeval very low-mass stars and brown dwarfs - IV. New L subdwarfs, Gaia astrometry, population properties, and a blue brown dwarf binary
• Uniform Forward-Modeling Analysis of Ultracool Dwarfs. II. Atmospheric Properties of 55 Late-T Dwarfs
• New ultracool subdwarfs identified in large-scale surveys using Virtual Observatory tools: Part I: UKIDSS LAS DR5 vs SDSS DR7
• A New Sample of Cool Subdwarfs from SDSS: Properties and Kinematics
• The discovery of a T6.5 subdwarf
• The Enigmatic Brown Dwarf WISEA J153429.75-104303.3 (aka "The Accident")
• New ultracool subdwarfs identified in large-scale surveys using Virtual Observatory tools: II. SDSS DR7 vs UKIDSS LAS DR6, SDSS DR7 vs UKIDSS LAS DR8, SDSS DR9 vs UKIDSS LAS DR10, and SDSS DR7 vs 2MASS
• A New Parallax Measurement for the Coldest Known Brown Dwarf
• Spectroscopic Follow-Up of Discoveries from the NEOWISE Proper Motion Survey
• VLT X-shooter spectroscopy of the nearest brown dwarf binary
• The HST large programme on $\omega$ Centauri -- V. Exploring the Ultracool Dwarf Population with Stellar Atmosphere and Evolutionary Modelling
• The first retrieval of a substellar subdwarf: A cloud-free SDSS J125637.13-022452.4
• Spectral energy distribution of M-subdwarfs: A study of their atmospheric properties
• Parallax of the L4.5 dwarf 2M1821$+$14 from high-precision astrometry with OSIRIS at GTC
• Near-infrared photometry of WISE J085510.74$-$071442.5
• Metallicity, temperature, and gravity scales of M subdwarfs
• Metal-Depleted Brown Dwarfs

Cited by in corpus (5)

• unTimely: a Full-sky, Time-Domain unWISE Catalog
• Exploring the Extremes: Characterizing a New Population of Old and Cold Brown Dwarfs
• Silicate Precursor Silane detected in Cold Low-Metallicity Brown Dwarf
• Optical Properties of Metal-poor T Dwarf Candidates
• Optical constraints on the coldest metal-poor population