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Related papers: 49 new T dwarfs identified using methane imaging

200 papers

Near-infrared spectroscopic observations of a sample of very cool, low-mass objects are presented with higher spectral resolution than in any previous studies. Six of the objects are L-dwarfs, ranging in spectral class from L2 to L8/9, and…

We explore the spectral and atmospheric properties of brown dwarfs cooler than the latest known T dwarfs. Our focus is on the yet-to-be-discovered free-floating brown dwarfs in the \teff range from $\sim$800 K to $\sim$130 K and with masses…

Astrophysics · Physics 2008-11-26 Adam Burrows , David Sudarsky , Jonathan Lunine

We present an analysis of low-resolution infrared spectra for 25 brown dwarf candidates in the NGC 1333 molecular cloud. Candidates were chosen on the basis of their association with the high column density cloud core, and near-infrared…

Astrophysics · Physics 2014-11-25 Bruce Wilking , Ayman Mikhail , Glenn Carlson , Michael Meyer , Thomas Greene

We present K- and L-band photometry obtained with the Keck I telescope for a representative sample of L and T dwarfs. These observations were motivated in part by the dominant role water and methane play in shaping the flux near 2 and 3…

Astrophysics · Physics 2009-11-06 D. C. Stephens , M. S. Marley , K. S. Noll , N. Chanover

We present spectroscopic follow-up observations of 68 red, faint candidates from our multi-epoch, multi-wavelength, previously published survey of NGC 2264. Using near-infrared spectra from VLT/KMOS, we measure spectral types and extinction…

Solar and Stellar Astrophysics · Physics 2021-09-01 Samuel Pearson , Aleks Scholz , Paula S Teixeira , Koraljka Mužić , Víctor Almendros-Abad

The aim of the project is to improve our knowledge on the low-mass and low-metallicity population to investigate the influence of metallicity of the stellar (and substellar) mass function. We present the results of a photometric and proper…

Solar and Stellar Astrophysics · Physics 2015-06-04 N. Lodieu , M. Espinoza Contreras , M. R. Zapatero Osorio , E. Solano , M. Aberasturi , E. L. Martín

Since October of 1995, employing Doppler spectroscopy astronomers have discovered as many as 20 giant planets and brown dwarfs, including companions to $\tau$ Boo, 51 Peg, $\upsilon$ And, 55 Cnc, $\rho$ CrB, 70 Vir, 16 Cyg B, and 47 UMa.…

We present deep VLT/NACO infrared imaging and spectroscopic observations of the brown dwarf 2MASSWJ1207334-393254, obtained during our on-going adaptive optics survey of southern young, nearby associations. This 25 MJup brown dwarf, located…

Astrophysics · Physics 2010-04-06 G. Chauvin , A. -M. Lagrange , C. Dumas , B. Zuckerman , D. Mouillet , I. Song , J. -L. Beuzit , P. Lowrance

Context. Brown dwarfs represent a sizable fraction of the stellar content of our Galaxy and populate the transition between the stellar and planetary mass regime. There is however no agreement on the processes responsible for their…

Astrophysics of Galaxies · Physics 2012-11-20 C. Alves de Oliveira , E. Moraux , J. Bouvier , G. Duchene , H. Bouy , T. Maschberger , P. Hudelot

Multiplicity is a key statistic for understanding the formation of very low mass (VLM) stars and brown dwarfs. Currently, the separation distribution of VLM binaries remains poorly constrained at small separations (<1 AU), leading to…

Solar and Stellar Astrophysics · Physics 2014-08-14 Daniella C. Bardalez Gagliuffi , Adam J. Burgasser , Christopher R. Gelino , Carl Melis , Cullen Blake

We present an analysis of low resolution infrared spectra for 20 brown dwarf candidates in the core of the $\rho$ Ophiuchi molecular cloud. Fifteen of the sources display absorption-line spectra characteristic of late-type stars. By…

Astrophysics · Physics 2009-10-31 Bruce A. Wilking , Thomas P. Greene , Michael R. Meyer

We present the results of a Keck/NIRSPEC follow-up survey of thirteen late-type T dwarfs (T6-T9), twelve of which have unusually red or blue J-H colors. Previous work suggests that J-H color outliers may represent the high-gravity,…

Solar and Stellar Astrophysics · Physics 2018-11-14 Sarah E. Logsdon , Gregory N. Mace , Ian S. McLean , Emily C. Martin

The census of the solar neighborhood is almost complete for stars and becoming more complete in the brown dwarf regime. Spectroscopic, photometric and kinematic characterization of nearby objects helps us to understand the local mass…

Solar and Stellar Astrophysics · Physics 2015-11-04 J. C. Beamín , V. D. Ivanov , D. Minniti , R. L. Smart , K. Muzic , R. A. Mendez , Y. Beletsky , A. Bayo , M. Gromadzki , R. Kurtev

With tens to hundreds of spectra of white dwarfs being taken each night from multi-object spectroscopic surveys, automated spectral classification is essential as part of efficient data processing. In this study, we design a neural network…

The space density of late M dwarfs, subtypes M7-M9.5, is not well determined. We applied the photo-type method to $iz$ photometry from the Sloan Digital Sky Survey and $YJHK$ photometry from the UKIRT Infrared Deep Sky Survey, over an…

Solar and Stellar Astrophysics · Physics 2019-03-22 S. Ahmed , S. J. Warren

Condensate clouds are a salient feature of L dwarf atmospheres, but have been assumed to play little role in shaping the spectra of the coldest T-type brown dwarfs. Here we report evidence of condensate opacity in the near-infrared spectrum…

In this paper, we describe how to use the Maximum Reduced Proper Motion method (Phan-Bao et al. 2003) to detect 57 nearby L and late-M dwarfs (d_phot <= 30 pc): 36 of them are newly discovered. Spectroscopic observations of 43 of the 57…

Solar and Stellar Astrophysics · Physics 2015-05-28 N. Phan-Bao

T-type brown dwarfs present an opportunity to explore atmospheres teeming with molecules such as H2O, CH4 and NH3, which exhibit a wealth of absorption features in the mid-infrared. With JWST, we can finally explore this chemistry in…

We aim at developing an efficient method to search for late-type subdwarfs (metal-depleted dwarfs with spectral types >M5) to improve the current statistics. Our objectives are: improve our knowledge of metal-poor low-mass dwarfs, bridge…

Solar and Stellar Astrophysics · Physics 2017-02-08 N. Lodieu , M. Espinoza Contreras , M. R. Zapatero Osorio , E. Solano , M. Aberasturi , E. L. Martin , C. Rodrigo

Recent observations of nearby star forming regions have offered evidence that young brown dwarfs undergo a period of mass accretion analogous to the T Tauri phase observed in young stars. Brown dwarf analogs to stellar protostars, however,…