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

Abstract

New near-infrared large-area sky surveys (e.g. UKIDSS, CFBDS, WISE) go deeper than 2MASS and aim at detecting brown dwarfs lurking in the Solar neighbourhood which are even fainter than the latest known T-type objects, so-called Y dwarfs. Using UKIDSS data, we have found a faint brown dwarf candidate with very red optical-to-near-infrared but extremely blue near-infrared colours next to the recently discovered nearby L dwarf SDSS J141624.08$+$134826.7. We check if the two objects are co-moving by studying their parallactic and proper motion and compare the new object with known T dwarfs. The astrometric measurements are consistent with a physical pair ($sep$$\approx$75 AU) at a distance $d$$\approx$8 pc. The extreme colour ($J$$-$$K$$\approx$$-$1.7) and absolute magnitude ($M_J$=17.78$\pm$0.46 and $M_K$=19.45$\pm$0.52) make the new object appear as one of the coolest (T${}_{eff}$$\approx$600 K) and nearest brown dwarfs, probably of late-T spectral type and possibly with a high surface gravity (log $g$$\approx$5.0).

accepted for publication as a Letter in Astronomy and Astrophysics, 4 pages, 7 figures, changed subtitle and discussion, former Fig. 4 removed, new Figs. 2, 6, and 7

References in corpus (14)

• The UKIRT Infrared Deep Sky Survey (UKIDSS)
• The Evolution of L and T Dwarfs in Color-Magnitude Diagrams
• The WFCAM Science Archive
• The UKIRT Infrared Deep Sky Survey Early Data Release
• Mid-Infrared Photometry of Cold Brown Dwarfs: Diversity in Age, Mass and Metallicity
• Discovery of 11 New T Dwarfs in the Two Micron All-Sky Survey, Including a Possible L/T Transition Binary
• Clouds, Gravity and Metallicity in Blue L dwarfs: The Case of 2MASS J11263991-5003550
• CFBDS J005910.90-011401.3: reaching the T-Y Brown Dwarf transition?
• A very cool brown dwarf in UKIDSS DR1
• The discovery of an M4+T8.5 binary system
• Exploring the substellar temperature regime down to ~550K
• Finding ultracool brown dwarfs with MegaCam on CFHT: method and first results
• SDSS J141624.08+134826.7: A Nearby Blue L Dwarf From the Sloan Digital Sky Survey
• Discovery of An Unusually Blue L Dwarf Within 10 pc of the Sun

Cited by in corpus (54)

• The Hawaii Infrared Parallax Program. I. Ultracool Binaries and the L/T Transition
• Further Defining Spectral Type "Y" and Exploring the Low-mass End of the Field Brown Dwarf Mass Function
• Weather on Other Worlds. II. Survey Results: Spots Are Ubiquitous on L and T Dwarfs
• The Field Substellar Mass Function Based on the Full-sky 20-pc Census of 525 L, T, and Y Dwarfs
• The discovery of a very cool, very nearby brown dwarf in the Galactic plane
• SpeX Spectroscopy of Unresolved Very Low Mass Binaries. II. Identification of Fourteen Candidate Binaries with Late-M/Early-L and T Dwarf Components
• Preliminary Trigonometric Parallaxes of 184 Late-T and Y Dwarfs and an Analysis of the Field Substellar Mass Function into the "Planetary" Mass Regime
• Photometry and Proper Motions of M, L, and T Dwarfs from the Pan-STARRS1 3$\pi$ Survey
• Clouds in the Coldest Brown Dwarfs: FIRE Spectroscopy of Ross 458C
• Uniform Atmospheric Retrieval Analysis of Ultracool Dwarfs II: Properties of 11 T-dwarfs
• Discovery of a Highly Unequal-Mass Binary T Dwarf with Keck Laser Guide Star Adaptive Optics: A Coevality Test of Substellar Theoretical Models and Effective Temperatures
• A Volume-Limited Sample of Ultracool Dwarfs. I. Construction, Space Density, and a Gap in the L/T Transition
• Doppler Imaging of Exoplanets and Brown Dwarfs
• The First Ultra-Cool Brown Dwarf Discovered by the Wide-field Infrared Survey Explorer
• The AllWISE Motion Survey, Part 2
• Discovery of an Unusually Red L-type Brown Dwarf
• A large spectroscopic sample of L and T dwarfs from UKIDSS LAS: peculiar objects, binaries, and space density
• The properties of the T8.5p dwarf Ross 458C
• Wide, Cool and Ultracool Companions to Nearby Stars from Pan-STARRS1
• A Comparison of Near-Infrared Photometry and Spectra for Y Dwarfs with a New Generation of Cool Cloudy Models
• CFBDSIR J1458+1013B: A Very Cold (>T10) Brown Dwarf in a Binary System
• The Properties of the 500 K Dwarf UGPS J072227.51-054031.2, and a Study of the Far-Red Flux of Cold Brown Dwarfs
• LHS 2803B: A very wide mid-T dwarf companion to an old M dwarf identified from Pan-STARRS1
• HIP 38939B: A New Benchmark T Dwarf in the Galactic Plane Discovered with Pan-STARRS1
• The sub-stellar birth rate from UKIDSS
• Self-consistent Models of Y Dwarf Atmospheres with Water Clouds and Disequilibrium Chemistry
• Blue not brown: UKIDSS T dwarfs with suppressed K-band flux
• DENIS J081730.0-615520: An overlooked mid-T dwarf in the solar neighborhood
• ULAS J141623.94+134836.3: a Blue T Dwarf Companion to a Blue L Dwarf
• The Hawaii Infrared Parallax Program. V. New T-Dwarf Members and Candidate Members of Nearby Young Moving Groups
• Retrieval of SDSS J1416+1348AB
• A Search for Photometric Variability in L and T type Brown Dwarf Atmospheres
• FIRE Spectroscopy of Five Late-type T Dwarfs Discovered with the Wide-field Infrared Survey Explorer
• The Hyperactive L Dwarf 2MASS J13153094-2649513: Continued Emission and a Brown Dwarf Companion
• SDSS J141624.08+134826.7: Blue L Dwarfs and Non-Equilibrium Chemistry
• Uniform Forward-Modeling Analysis of Ultracool Dwarfs. II. Atmospheric Properties of 55 Late-T Dwarfs
• A Search for Companions to Brown Dwarfs in the Taurus and Chamaeleon Star Forming Regions
• An overlooked brown dwarf neighbour (T7.5 at d~5pc) of the Sun and two additional T dwarfs at about 10pc
• WISEP J180026.60+013453.1: A Nearby Late L Dwarf Near the Galactic Plane
• Resolved Spectroscopy of a Brown Dwarf Binary at the T Dwarf/Y Dwarf Transition
• Resolved Spectroscopy of M Dwarf/L Dwarf Binaries. IV. Discovery of an M9 + L6 BInary Separated by Over 100 AU
• The Late-Type Extension to MoVeRS (LaTE-MoVeRS): Proper motion verified low-mass stars and brown dwarfs from SDSS, 2MASS, and WISE
• Physical properties and trigonometric distance of the peculiar dwarf WISE J181005.5$-$101002.3
• Resolved Spectroscopy of the T8.5 and Y0-0.5 Binary WISEPC J121756.91+162640.2AB
• Spitzer Light Curves of the Young, Planetary-Mass TW Hya Members 2MASS J11193254-1137466AB and WISEA J114724.10-204021.3
• Parallaxes of Cool Objects with WISE: Filling in for Gaia
• A non-uniform distribution of the nearest brown dwarfs
• CWISE J014611.20-050850.0AB: The Widest Known Brown Dwarf Binary in the Field
• Wide companions to M and L subdwarfs with Gaia and the Virtual Observatory
• Increasing the census of L and T dwarfs in wide binary and multiple systems using Dark Energy Survey DR1 and Gaia DR2 data
• Optical constraints on the coldest metal-poor population
• Search for Close Stellar Encounters with the Solar System from Data on Nearby Dwarfs
• Benchmark brown dwarfs -- I. A blue M2 + T5 wide binary and a probable young [M4 + M4] + [T7 + T8] hierarchical quadruple
• Disentangling the Signatures of Blended-Light Atmospheres in L/T Transition Brown Dwarfs