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Related papers: The Intermediate Age Brown Dwarf LP 944-20

200 papers

Astrometric monitoring of the nearby early-L dwarf DE0823$-$49 has revealed a low-mass companion in a 248-day orbit that was announced in an earlier work. Here, we present new astrometric and spectroscopic observations that allow us to…

Solar and Stellar Astrophysics · Physics 2015-07-01 J. Sahlmann , A. J. Burgasser , E. L. Martín , P. F. Lazorenko , D. C. Bardalez Gagliuffi , M. Mayor , D. Ségransan , D. Queloz , S. Udry

We report the discovery of a brown dwarf companion to the young M dwarf 1RXS J235133.3+312720 as part of a high contrast imaging search for planets around nearby young low-mass stars with Keck-II/NIRC2 and Subaru/HiCIAO. The 2.4" (~120 AU)…

Solar and Stellar Astrophysics · Physics 2015-06-05 Brendan P. Bowler , Michael C. Liu , Evgenya L. Shkolnik , Trent J. Dupuy , Lucas A. Cieza , Adam L. Kraus , Motohide Tamura

We aim to provide a detailed characterization of near-infrared spectra for young LT brown dwarfs, including robust spectral typing, calibrating spectral indices, identifying possible binaries, and selecting suitable spectral standards. We…

Solar and Stellar Astrophysics · Physics 2024-05-29 L. Piscarreta , K. Mužić , V. Almendros-Abad , A. Scholz

We have imaged two bona-fide brown dwarfs with TReCS/GEMINI-S and find mid-infrared excess emission that can be explained by optically thick dust disk models. In the case of the young ($\approx$2Myr) Cha H$\alpha$1 we measure fluxes at…

We have monitored the position of the cool Y dwarf WISEPA J182831.08+265037.8 using a combination of ground- and space-based telescopes and have determined its distance to be 11.2$_{-1.0}^{+1.3}$ pc. Its absolute H magnitude,…

We present the results of a search for brown dwarfs (BDs) and very low mass (VLM) stars in the 625 Myr-old, metal-rich ([Fe/H]=0.14) Hyades cluster. We performed a deep (I=23, z=22.5) photometric survey over 16 deg$^2$ around the cluster…

Astrophysics · Physics 2009-11-13 Jerome Bouvier , Tim Kendall , Gwendolyn Meeus

The LHS 1610 system consists of a nearby ($d=9.7$ pc) M5 dwarf hosting a candidate brown dwarf companion in a $10.6$ day, eccentric ($e \sim 0.37$) orbit. We confirm this brown dwarf designation and estimate its mass ($ 49.5_{-3.5}^{+4.3}$…

Juvenile ultracool dwarfs are late spectral type objects (later than ~M6) with ages between 10 Myr and several 100 Myr. Their age-related properties lie intermediate between very low mass objects in nearby star-forming regions (ages 1-5…

We report individual dynamical masses of $66.92 \pm 0.36 \; M_{Jup}$ and $53.25 \pm 0.29 \; M_{Jup}$ for the binary brown dwarfs $\varepsilon$ Indi Ba and Bb, measured from long term ($\approx 10$ yr) relative orbit monitoring and absolute…

Solar and Stellar Astrophysics · Physics 2022-06-01 Minghan Chen , Yiting Li , Timothy D. Brandt , Trent J. Dupuy , Cátia V. Cardoso , Mark J. McCaughrean

Using the Hubble Space Telescope, the 4 m Blanco telescope at the Cerro Tololo Inter-American Observatory, and the Spitzer Space Telescope, we have performed deep imaging from 0.8 to 8 um of the southern subcluster in the Chamaeleon I…

We present a comprehensive analysis of 20 T and Y dwarfs using spectroscopy from the NIRSpec CLEAR/PRISM and MIRI LRS instruments on the James Webb Space Telescope. To characterize the atmospheric parameters, we utilize two atmospheric…

Solar and Stellar Astrophysics · Physics 2024-11-15 Zhijun Tu , Shu Wang , Jifeng Liu

We present new evidence for a problem with cooling rates predicted by substellar evolutionary models that implies model-derived masses in the literature for brown dwarfs and directly imaged planets may be too high. Based on our dynamical…

Solar and Stellar Astrophysics · Physics 2015-06-19 Trent J. Dupuy , Michael C. Liu , Michael J. Ireland

We report multi-epoch radial velocities, rotational velocities, and atmospheric parameters for 37 T-type brown dwarfs observed with Keck/NIRSPEC. Using a Markov Chain Monte Carlo forward-modeling method, we achieve median precisions of 0.5…

Studying the accretion process in very low-mass objects has important implications for understanding their formation mechanism. Many nearby late-M dwarfs that have previously been identified in the field are in fact young brown dwarf…

Solar and Stellar Astrophysics · Physics 2020-03-04 D. Nguyen-Thanh , N. Phan-Bao , S. J. Murphy , M. S. Bessell

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 report on nine wide common proper motion systems containing late-type M, L, or T companions. We confirm six previously reported companions, and identify three new systems. The ages of these systems are determined using diagnostics for…

The nearby brown dwarf LP 944-20 has been monitored for radial velocity variability at optical and near-infrared wavelengths using the VLT/UVES and the Keck/NIRSPEC spectrographs, respectively. The UVES radial velocity data obtained over 14…

Astrophysics · Physics 2009-11-11 E. L. Martin , E. Guenther , M. R. Zapatero Osorio , H. Bouy , R. Wainscoat

We present spectral and kinematic evidence that 2MASS J06085283-2753583 (M8.5gamma) is a member of the beta Pictoris Moving Group (BPMG, age ~12 Myr), making it the latest-type known member of this young, nearby association. We confirm…

Solar and Stellar Astrophysics · Physics 2015-03-17 Emily L. Rice , Jacqueline K. Faherty , Kelle L. Cruz

The nearby late M star Gliese 569B was recently found by adaptive optics imaging to be a double with separation ~1 AU. To explore the orbital motion and masses, we have undertaken a high resolution (~0.05 arcsec) astrometric study. Images…