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Related papers: Spectral characterization of young LT dwarfs

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We obtained medium-resolution near-infrared spectra of seven young M9.5-L3 dwarfs classified in the optical. We aim to confirm the low surface gravity of the objects in the NIR. We also test whether atmospheric models correctly represent…

Solar and Stellar Astrophysics · Physics 2015-06-18 E. Manjavacas , M. Bonnefoy , J. E. Schlieder , F. Allard , P. Rojo , B. Goldman , G. Chauvin , D. Homeier , N. Lodieu , T. Henning

Brown dwarfs are essential probes of stellar and planetary formation, yet their low luminosities pose challenges for detection at large Galactic distances. The James Webb Space Telescope (JWST), with its unprecedented near-infrared…

Solar and Stellar Astrophysics · Physics 2025-10-03 Zhijun Tu , Shu Wang , Xiaodian Chen , Jifeng Liu

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

Brown dwarfs undergo little change in near-infrared luminosity while cooling from L to T spectral types, making the L/T transition (spectral types $\approx$L9--T6) an ideal region to examine the differences in photometry for binary and…

Solar and Stellar Astrophysics · Physics 2019-12-19 Madeline R. Wilson , William M. J. Best

Using a simulated disk brown dwarf (BD) population, we find that new large area infrared surveys are expected to identify enough BDs covering wide enough mass--age ranges to potentially measure the mass function down to ~0.03Mo, and the BD…

Accurate parallax measurements allow us to determine physical properties of brown dwarfs, and help us to constrain evolutionary and atmospheric models, break the age-mass degeneracy and reveal unresolved binaries. We measured absolute…

Solar and Stellar Astrophysics · Physics 2015-06-17 E. Manjavacas , B. Goldman , S. Reffert , T. Henning

We report the discovery of four field methane (T-type) brown dwarfs using 2MASS survey data. One additional methane dwarf, previously discovered by SDSS, was also identified. Near-infrared spectra clearly show the 1.6 and 2.2 um CH4…

We present here medium resolution (\lambda /\Delta\lambda\sim1200) H- and K-band spectra of M type dwarf stars covering the wavelength range 1.50 - 1.80 {\mu}m and 1.95 - 2.45 {\mu}m. The sample includes 53 dwarf stars (M0V-M7V) from new…

Solar and Stellar Astrophysics · Physics 2021-07-30 Dhrimadri Khata , Soumen Mondal , Ramkrishna Das , Supriyo Ghosh , Samrat Ghosh

Young brown dwarfs serve as analogues of giant planets and provide benchmarks for atmospheric and formation models. JWST has enabled access to near-infrared spectra of brown dwarfs with unprecedented sensitivity. We aim to constrain their…

Earth and Planetary Astrophysics · Physics 2025-11-05 D. González Picos , S. de Regt , S. Gandhi , N. Grasser , I. A. G. Snellen

(Abridged) We have completed the first systematic survey for disks around spectroscopically identified young brown dwarfs and very low mass stars. We have obtained L'-band (3.8 um) imaging for 38 very cool objects in IC 348 and Taurus. Our…

Astrophysics · Physics 2008-11-26 Michael C. Liu , Joan Najita , Alan T. Tokunaga

We present the identification and characterization of 15 mid-to-late T dwarf candidates in the Euclid Quick Release 1 (Q1) dataset, based on a combined photometric and spectroscopic analysis. Candidates were initially selected via…

Cold, substellar objects such as brown dwarfs have long been recognized as contaminants in color-selected samples of active galactic nuclei (AGNs). In particular, their near- to mid-infrared colors (1-5 $\mu$m) can closely resemble the…

Astrophysics of Galaxies · Physics 2023-11-13 Danial Langeroodi , Jens Hjorth

We present preliminary trigonometric parallaxes of 184 late-T and Y dwarfs using observations from Spitzer (143), USNO (18), NTT (14), and UKIRT (9). To complete the 20-pc census of $\ge$T6 dwarfs, we combine these measurements with…

We have performed deep, wide-field imaging on a ~0.4 deg^2 field in the Pleiades (Melotte 22). The selected field was not yet target of a deep search for low mass stars and brown dwarfs. Our limiting magnitudes are R ~ 22mag and I ~ 20mag,…

We conducted a search for brown dwarf candidates in a James Webb Space Telescope deep field around A2744 to investigate the space density of these objects at kiloparsec distances. Our methodology employed an initial selection based on…

Solar and Stellar Astrophysics · Physics 2026-02-17 D. H. Li , Z. H. Zhang , H. H. Peng , M. C. Galvez-Ortiz , S. Y. Zhou , H. R. A. Jones

We have generated new, self-consistent spectral and atmosphere models for the effective temperature range 600 K to 1300 K thought to encompass the known T dwarfs. For the first time, theoretical models are compared with a {\it family} of…

We present additional analysis of the classification system presented in Allers & Liu (2013). We refer the reader to Allers & Liu (2013) for a detailed discussion of our near-IR spectral type and gravity classification system. Here, we…

Astrophysics of Galaxies · Physics 2013-07-30 K. N. Allers , Michael C. Liu

We report the discovery of seven hitherto unknown L-dwarfs found as a result of a spectroscopic search for distant AGB stars. Their far-red and near-infrared colours are very similar to known dwarfs of the same spectral type. One new object…

Astrophysics · Physics 2008-11-26 T. R. Kendall , N. Mauron , M. Azzopardi , K. Gigoyan

[ABRIDGED] We report the results of a $J$ band search for cloud-related variability in the atmospheres of 62 L4-T9 dwarfs using the Du Pont 2.5-m telescope at Las Campanas Observatory and the Canada France Hawaii Telescope on Mauna Kea. We…

Solar and Stellar Astrophysics · Physics 2015-06-19 Jacqueline Radigan , David Lafrenière , Ray Jayawardhana , Etienne Artigau

We present a new suite of atmosphere models with flexible cloud parameters to investigate the effects of clouds on brown dwarfs across the L/T transition. We fit these models to a sample of 13 objects with well-known masses, distances, and…

Solar and Stellar Astrophysics · Physics 2021-06-21 Laci Shea Brock , Travis Barman , Quinn M. Konopacky , Jordan M. Stone