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Related papers: The NIRSPEC Ultracool Dwarf Radial Velocity Survey

200 papers

We present predictions for the numbers of ultra--cool dwarfs in the Galactic disk population that could be detected by the WFCAM/UKIDSS Large Area Survey and Ultra Deep Survey. Simulated samples of objects are created with masses and ages…

Astrophysics · Physics 2009-11-11 N. R. Deacon , N. C. Hambly

Doppler-based planet surveys have discovered numerous giant planets but are incomplete beyond several AU. At larger star-planet separations, direct planet detection through high-contrast imaging has proven successful, but this technique is…

Earth and Planetary Astrophysics · Physics 2014-01-23 Benjamin T. Montet , Justin R. Crepp , John Asher Johnson , Andrew W. Howard , Geoffrey W. Marcy

We present low-resolution near-infrared spectra of discoveries from an all-sky proper motion search conducted using multi-epoch data from the Wide-field Infrared Survey Explorer. Using the data from NEOWISE, along with the AllWISE catalog,…

Solar and Stellar Astrophysics · Physics 2019-10-23 Jennifer J. Greco , Adam C. Schneider , Michael C. Cushing , J. Davy Kirkpatrick , Adam J. Burgasser

We present the discovery of 34 comoving systems containing an ultra-cool dwarf found by means of the NOIRLab Source Catalog (NSC) DR2. NSC's angular resolution of $\sim$1" allows for the detection of small separation binaries with…

The Canada-France Brown Dwarf Survey is a wide eld survey for cool brown dwarfs conducted with the MegaCam camera on the CFHT telescope. Our objectives are to nd ultracool brown dwarfs and to constrain the eld brown dwarf mass function from…

Astrophysics · Physics 2009-11-13 C. Reyle , P. Delorme , X. Delfosse , T. Forveille , C. Willott , L. Albert , E. Artigau

About a dozen substellar companions orbiting young stellar objects or pre-main sequence stars at several hundred au have been identified in the last decade. These objects are interesting both due to the uncertainties surrounding their…

We present preliminary results of an imaging survey for companions to low-luminosity dwarfs with spectral types ranging from M7 to L9. A K-band study with the Near Infrared Camera (NIRC) at the Keck telescope discriminates against…

Astrophysics · Physics 2007-05-23 D. W. Koerner , J. Davy Kirkpatrick , I. N. Reid , J. Gizis

Recent monitoring programs of ultra cool field M and L dwarfs (low mass stars or brown dwarfs) have uncovered low amplitude photometric I-band variations which may be associated with an inhomogeneous distribution of photospheric…

Astrophysics · Physics 2009-11-07 C. A. L. Bailer-Jones , M. Lamm

Benchmark brown dwarfs in wide binary systems are crucial for characterizing substellar objects and calibrating atmospheric and evolutionary models. However, brown dwarf benchmarks with subsolar metallicity, very cool temperatures, or…

We present the discovery of the first T dwarf + white dwarf binary system LSPM 1459+0857AB, confirmed through common proper motion and spectroscopy. The white dwarf is a high proper motion object from the LSPM catalogue that we confirm…

I have undertaken a comprehensive statistical investigation of the ultracool dwarf companion distribution (spectral type M6 and later). Utilizing a Bayesian algorithm, I tested models of the companion distribution against data from an…

Astrophysics · Physics 2010-01-28 Peter R. Allen

The census of planets around M dwarfs in the solar neighbourhood meets two challenges: detecting the best targets for the future characterisation of planets with ELTs, and studying the statistics of planet occurrence that are crucial to…

We present radial velocity (RV) measurements of our sample of 40 M dwarfs from our planet search programme with VLT+UVES begun in 2000. Although with our RV precision down to 2 - 2.5 m/s and timebase line of up to 7 years, we are capable of…

Earth and Planetary Astrophysics · Physics 2018-11-20 M. Zechmeister , M. Kürster , M. Endl

We have used NSF's Karl G. Jansky Very Large Array (VLA) to observe a sample of five known radio-emitting late L and T dwarfs ranging in age from ~0.2 - 3.4Gyr. We observed each target for seven hours, extending to higher frequencies than…

Solar and Stellar Astrophysics · Physics 2018-08-09 Melodie Kao , Gregg Hallinan , J. Sebastian Pineda , David Stevenson , Adam Burgasser

We define an enhanced spectral classification scheme for M dwarf stars, and use it to derive spectral classification of 104 northern stars with proper motions larger than 0.5"/yr which we discovered in a survey of high proper motion stars…

Astrophysics · Physics 2009-11-07 Sebastien Lepine , R. Michael Rich , Michael M. Shara

We present the results of a radial velocity (RV) survey of 14 brown dwarfs (BDs) and very low-mass (VLM) stars in the Upper Scorpius OB association (UScoOB) and 3 BD candidates in the rho Ophiuchi dark cloud core. We obtained…

Astrophysics · Physics 2009-11-11 Ryuichi Kurosawa , Tim J. Harries , S. P. Littlefair

We have used the NICMOS NIC1 camera on the Hubble Space Telescope to obtain high angular resolution images of 51 ultracool dwarfs in the immediate Solar Neighbourhood. Nine systems are resolved as binary, with component separations from 1.5…

Astrophysics · Physics 2008-11-26 I. N. Reid , E. Lewitus , P. R. Allen , Kelle L. Cruz , Adam J. Burgasser

We combine 131 new medium-resolution (R~2000) J-band spectra of M, L, and T dwarfs from the Keck NIRSPEC Brown Dwarf Spectroscopic Survey (BDSS) with 97 previously published BDSS spectra to study surface-gravity-sensitive indices for 228…

We selected brown dwarf candidates from the seventh Data Release of the Sloan Digital Sky Survey (SDSS DR7) with new photometric selectioncriteria based on a parameteriaztion of well-known L and T dwarfs. Then we confirmed their status with…

Astrophysics of Galaxies · Physics 2010-01-21 Z. H. Zhang , H. R. A. Jones , D. J. Pinfield , R. S. Pokorny , Z. Han

Brown dwarf spectra are rich in information revealing of the chemical and physical processes operating in their atmospheres. We apply a recently developed atmospheric retrieval tool to an ensemble of late T-dwarf (600-800K) near infrared…

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