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Related papers: Brown Dwarfs as Galactic Chronometers

200 papers

The ages of the most common stars - low-mass (cool) stars like the Sun, and smaller - are difficult to derive because traditional dating methods use stellar properties that either change little as the stars age or are hard to measure. The…

Solar and Stellar Astrophysics · Physics 2015-06-23 Soren Meibom , Sydney A. Barnes , Imants Platais , Ronald L. Gilliland , David W. Latham , Robert D. Mathieu

In its all-sky survey, Gaia will monitor astrometrically and photometrically millions of main-sequence stars with sufficient sensitivity to brown dwarf companions within a few AUs from their host stars and to transiting brown dwarfs on very…

Solar and Stellar Astrophysics · Physics 2014-06-06 A. Sozzetti

We present new white dwarf cooling models which incorporate an accurate outer boundary condition based on new opacity and detailed radiative transfer calculations. We find that helium atmosphere dwarfs cool considerably faster than has…

Astrophysics · Physics 2011-02-11 Brad M. S. Hansen

The multiplicity properties of brown dwarfs are critical empirical constraints for formation theories, while multiples themselves provide unique opportunities to test evolutionary and atmospheric models and examine empirical trends. Studies…

The survey of the mid-infrared sky by the Wide-field Infrared Survey Explorer (WISE) led to the discovery of extremely cold low-mass brown dwarfs, classified as Y dwarfs, which extend the T class to lower temperatures. Twenty-four Y dwarfs…

Solar and Stellar Astrophysics · Physics 2017-06-28 S. K. Leggett , P. Tremblin , T. L. Esplin , K. L. Luhman , Caroline V. Morley

To better understand the potential habitability of planets orbiting brown dwarfs, this work presents a new set of equilibrium temperature evolution tracks. Unlike most previous work that relied on analytic scaling relationships for brown…

Earth and Planetary Astrophysics · Physics 2026-03-31 Kayla J. Smith , Mark S. Marley

Stellar ages are extremely difficult to determine and often subject to large uncertainties, especially for field low-mass stars. We plan to carry out a calibration of the decrease in high-energy emissions of low-mass GKM stars with time,…

Solar and Stellar Astrophysics · Physics 2015-05-28 A. Garcés , S. Catalán , I. Ribas

The last few years has seen a dramatic increase in the number of exoplanets known and in the range of methods for characterising their atmospheric properties. At the same time, new discoveries of increasingly cooler brown dwarfs have pushed…

Earth and Planetary Astrophysics · Physics 2015-06-23 Jeremy Bailey

The primary goal of the Ariel space telescope is to conduct the biggest spectroscopic survey of transiting exoplanets to characterize their atmospheres and weather. We propose to extend the Ariel survey to another domain of alien…

Earth and Planetary Astrophysics · Physics 2026-05-29 Roman Akhmetshyn , Nicolas B Cowan , Sarah Casewell

Up to now, most planet search projects have concentrated on F to K stars. In order to considerably widen the view, we have stated a survey for planets of old, nearby brown dwarfs and very low mass stars. Using UVES, we have observed 26…

Astrophysics · Physics 2011-05-23 Eike W. Guenther , Guenther Wuchterl

We present a grid of models of accreting brown dwarf systems with circumstellar discs. The calculations involve a self-consistent solution of both vertical hydrostatic and radiative equilibrium along with a sophisticated treatment of dust…

Solar and Stellar Astrophysics · Physics 2015-05-19 Nathan Mayne , Tim Harries

Brown dwarfs can serve as both clocks and chemical tracers of the evolutionary history of the Milky Way due to their continuous cooling and high sensitivity of spectra to composition. We focus on brown dwarfs in globular clusters that host…

Solar and Stellar Astrophysics · Physics 2022-05-11 Roman Gerasimov , Adam J. Burgasser , Derek Homeier , Luigi R. Bedin , Jon M. Rees , Michele Scalco , Jay Anderson , Maurizio Salaris

In this work we examine M dwarf rotation rates at a range of ages to establish benchmarks for Mdwarf gyrochronology. This work includes a sample of 713 spectroscopically-classified M0-M8 dwarfs with new rotation rates measured from K2 light…

Solar and Stellar Astrophysics · Physics 2021-08-11 Mark Popinchalk , Jacqueline K. Faherty , Rocio Kiman , Jonathan Gagné , Jason L. Curtis , Ruth Angus , Kelle L. Cruz , Emily L. Rice

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 describe a new multi-colour proper motion survey for cool white dwarfs (CWDs). The observational database consists of ~300 digitally scanned Schmidt plates in ESO/SERC field 287. The entire survey procedure, from the raw Schmidt plate…

Astrophysics · Physics 2009-10-31 R. A. Knox , M. R. S. Hawkins , N. C Hambly

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

While brown dwarfs show similarities with stars in their early life, their spin evolution is much more akin to that of planets. We have used lightcurves from the K2 mission to measure new rotation periods for 18 young brown dwarfs in the…

Earth and Planetary Astrophysics · Physics 2018-06-27 Aleks Scholz , Keavin Moore , Ray Jayawardhana , Suzanne Aigrain , Dawn Peterson , Beate Stelzer

Theories that attempt to unify the four fundamental interactions and alternative theories of gravity predict time and/or spatial variation of the fundamental constants of nature. Different versions of these theories predict different…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-14 Susana J. Landau

Abridged. White dwarf stars are the final evolutionary stage of the vast majority of stars, including our Sun. The study of white dwarfs has potential applications to different fields of astrophysics. In particular, they can be used as…

Solar and Stellar Astrophysics · Physics 2016-08-09 Leandro G. Althaus , Alejandro H. Córsico , Jordi Isern , Enrique García-Berro

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…

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