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Related papers: White Dwarf Spectra and Atmosphere Models

200 papers

As dense and hot bodies with a well-understood equation of state, white dwarfs offer a unique opportunity to investigate new physics. In this paper, we examine the role of dark sectors, which are extensions of the Standard Model of particle…

High Energy Physics - Phenomenology · Physics 2023-08-31 Jaime Hoefken Zink , Maura E. Ramirez-Quezada

Numerous observational evidence has suggested the presence of active meteorology in the atmospheres of brown dwarfs. A near-infrared brightness variability has been observed. Clouds have a major role in shaping the thermal structure and…

Earth and Planetary Astrophysics · Physics 2022-05-04 Maxence Lefèvre , Xianyu Tan , Elspeth K. H. Lee , R. T. Pierrehumbert

An Earth-like exoplanet orbiting a white dwarf would be exposed to different UV environments than Earth, influencing both its atmospheric photochemistry and UV surface environment. Using a coupled 1D climate-photochemistry code we model…

Earth and Planetary Astrophysics · Physics 2018-08-08 Thea Kozakis , Lisa Kaltenegger , D. W. Hoard

Brown Dwarf atmosphere are a chemically extremely rich, one example being the formation of clouds driven by the phase-non-equilibrium of the atmospheric gas. Cloud formation modelling is an integral part of any atmosphere simulation used to…

Solar and Stellar Astrophysics · Physics 2014-07-18 Christiane Helling

Diffusion coefficients are essential microphysics input for modeling white dwarf evolution, as they impact phase separation at crystallization and sedimentary heat sources. Present schemes for computing diffusion coefficients are accurate…

Solar and Stellar Astrophysics · Physics 2022-04-06 M. E. Caplan , E. B. Bauer , I. F. Freeman

Spectral evolution models are a widely used tool for determining the stellar content of galaxies. I provide a review of the latest developments in stellar atmosphere and evolution models, with an emphasis on massive stars. In contrast to…

Solar and Stellar Astrophysics · Physics 2015-05-14 Claus Leitherer

The space density of white dwarfs is highly uncertain even nearby. This results from the fact that the known sample of white dwarfs is largely incomplete in part because most white dwarfs have been discovered as by-products in non-dedicated…

Astrophysics · Physics 2007-05-23 L. Morales-Rueda , P. J. Groot , R. Napiwotzki , J. Drew , the EGAPS collaboration

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

Most of low- and intermediate-mass stars that populate the Universe will end their lives as white dwarf stars. These ancient stellar remnants have encrypted inside a precious record of the evolutionary history of the progenitor stars,…

Solar and Stellar Astrophysics · Physics 2014-12-23 A. H. Córsico

We present results of modeling of spectra of M-, L-, T-dwarfs. Theoretical spectra are fitted to observed spectra to study the main parameters of the low-mass objects beyond the bottom of Main Sequence. Application of ``lithium'' and…

Astrophysics · Physics 2007-05-23 Yakiv V. Pavlenko

White dwarf stars are the final stage of most stars, born single or in multiple systems. We discuss the identification, magnetic fields, and mass distribution for white dwarfs detected from spectra obtained by the Sloan Digital Sky Survey…

Solar and Stellar Astrophysics · Physics 2017-09-06 S. O. Kepler , Alejandra Daniela Romero , Ingrid Pelisoli , Gustavo Ourique

Given the importance of white dwarfs (WDs) in many fields of modern astrophysics, the precise knowledge of the actual degree of accuracy of the associated theoretical predictions is a primary task. In the first paper of a series dedicated…

Astrophysics · Physics 2009-11-13 P. G. Prada Moroni , O. Straniero

We discuss the feasibility of using astrophysical observations of white dwarfs as probes of fundamental physics. We quantify the effects of varying fundamental couplings on the white dwarf mass-radius relation in a broad class of…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-17 D. M. N. Magano , J. M. A. Vilas Boas , C. J. A. P. Martins

In the light of the recent and unexpected discovery of a brand new type of white dwarfs, those with carbon-dominated atmospheres, we examine the asteroseismological potential of such stars. The motivation behind this is based on the…

Astrophysics · Physics 2009-11-13 G. Fontaine , P. Brassard , P. Dufour

Observational facilities allow now the detection of optical and IR spectra of young M- and L-dwarfs. This enables empirical comparisons with old M- and L- dwarfs, and detailed studies in comparison with synthetic spectra. While classical…

Cool white dwarfs with Teff < 6000 K are the remnants of the oldest stars that existed in our Galaxy. Their atmospheres, when properly characterized, can provide valuable information on white dwarf evolution and ultimately star formation…

Solar and Stellar Astrophysics · Physics 2012-10-12 Piotr M. Kowalski , Didier Saumon , Jay Holberg , Sandy Leggett

We describe a new software package capable of predicting the spectra of solar-system planets, exoplanets, brown dwarfs and cool stars. The Versatile Software for Transfer of Atmospheric Radiation (VSTAR) code combines a line-by-line…

Earth and Planetary Astrophysics · Physics 2015-05-30 Jeremy Bailey , Lucyna Kedziora-Chudczer

The method and results of the computation of the model atmospheres and spectral energy distributions of chemically peculiar stars, are discussed. The models are computed with a special consideration of the particular problems encountered…

Astrophysics · Physics 2007-05-23 Yakiv V. Pavlenko

Practically all known planet hosts will evolve into white dwarfs, and large parts of their planetary systems will survive this transition - the same is true for the solar system beyond the orbit of Mars. Spectroscopy of white dwarfs…

Dense, He-rich atmospheres of cool white dwarfs represent a challenge to the modeling. This is because these atmospheres are constituted of a dense fluid in which strong multi-atomic interactions determine their physics and chemistry.…

Solar and Stellar Astrophysics · Physics 2016-10-25 Piotr M. Kowalski , Simon Blouin , Patrick Dufour
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