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Related papers: White Dwarf Spectra and Atmosphere Models

200 papers

Clouds and hazes are important throughout our solar system and in the atmospheres of brown dwarfs and extrasolar giant planets. Among the brown dwarfs, clouds control the colors and spectra of the L-dwarfs; the disappearance of clouds helps…

Astrophysics · Physics 2007-05-23 M. S. Marley , A. S. Ackerman

This chapter reviews our current knowledge of metal-poor ultracool dwarfs with spectral types later than M7. The current census of M, L, and T subdwarfs is explored. The main colour trends of subdwarfs from the optical to the mid-infrared…

Solar and Stellar Astrophysics · Physics 2018-12-05 Nicolas Lodieu

White dwarf and pre-white dwarf atmospheres are one of the best examples for the application of Stark broadening research results in astrophysics, due to plasma conditions very favorable for this line broadening mechanism. For example in…

Solar and Stellar Astrophysics · Physics 2018-03-14 Milan S. Dimitrijevic , Andjelka Kovacevic , Zoran Simic , Sylvie Sahal-Brechot

Clouds seem like an every-day experience. But -- do we know how clouds form on brown dwarfs and extra-solar planets? How do they look like? Can we see them? What are they composed of? Cloud formation is an old-fashioned but still…

Astrophysics · Physics 2014-11-17 Christiane Helling

At present, a large number of pulsating white dwarf (WD) stars is being discovered either from Earth-based surveys such as the Sloan Digital Sky Survey, or through observations from space (e.g., the Kepler mission). The asteroseismological…

Solar and Stellar Astrophysics · Physics 2017-03-06 Alejandro H. Córsico

Red subdwarfs in binary systems are crucial for both model calibration and spectral classification. We search for red subdwarfs in binary systems from a sample of high proper motion objects with Sloan digital Sky Survey spectroscopy. We…

Irradiated brown dwarfs (BDs) provide natural laboratories to test our understanding of substellar and irradiated atmospheres. A handful of short-period BDs around white dwarfs (WDs) have been observed, but the uniquely intense UV-dominated…

Solar and Stellar Astrophysics · Physics 2021-01-06 Joshua D. Lothringer , Sarah L. Casewell

Close white dwarf binaries (CWDBs) are considered to be progenitors of several exotic astronomical phenomena (e.g., type Ia supernovae, cataclysmic variables). These violent events are broadly used in studies of general relativity and…

Instrumentation and Methods for Astrophysics · Physics 2024-10-02 Genghao Liu , Baitian Tang , Liangliang Ren , Chengyuan Li , Sihao Cheng , Weikai Zong , Jianning Fu , Bo Ma , Cheng Xu , Yiming Hu

Spectral densities encode the relevant information characterising the system-environment interaction in an open-quantum system problem. Such information is key to determining the system's dynamics. In this work, we leverage the potential of…

Quantum Physics · Physics 2024-03-13 Jessica Barr , Giorgio Zicari , Alessandro Ferraro , Mauro Paternostro

We discuss some of our current knowledge of the mass distribution of DA and non-DA stars using various methods for measuring white dwarf masses including spectroscopic, trigonometric parallax, and gravitational redshift measurements, with a…

Astrophysics · Physics 2007-05-23 P. Bergeron , A. Gianninas , S. Boudreault

This paper reviews the physics of stars, the type, structure, evolution and stability. Simple thermodynamics and statistical mechanics are used to show the inner working of white dwarf and neutron stars. The major concentration of the paper…

Popular Physics · Physics 2024-03-21 Anuj Chaudhri

The atmospheres of cool, helium-rich white dwarfs constitute an exotic and poorly explored physical regime of stellar atmospheres. Under physical conditions where the temperature varies from $\rm 1000K$ to $\rm 10000K$, the density can…

Astrophysics · Physics 2007-05-23 P. M. Kowalski , D. Saumon , S. Mazevet

This White Paper, submitted to the National Academy of Sciences' Astro2010 Decadal Review Committee, focuses on 2 central themes in the study of young brown dwarfs -- their formation mechanism and disk characteristics -- which are of direct…

In the vast expanse of our galaxy, white dwarfs (WDs) are natural sentinels, capturing the enigmatic dark matter (DM) particles that incessantly traverse their interiors. These celestial bodies provide a unique vantage point for probing…

High Energy Physics - Phenomenology · Physics 2024-06-06 Jia-Shu Niu

The white dwarf luminosity function, which provides information about their cooling, has been measured with high precision in the past few years. Simulations that include well known Standard Model physics give a good fit to the data. This…

High Energy Physics - Phenomenology · Physics 2015-06-15 Herbert K. Dreiner , Jean-François Fortin , Jordi Isern , Lorenzo Ubaldi

Pulsation modes have recently been observed in a handful of white dwarf (WD) primaries of cataclysmic variables, allowing an interesting new probe into the structure of accreting WD's. We briefly discuss the seismology of these objects, how…

Astrophysics · Physics 2007-05-23 Phil Arras , Dean Townsley , Lars Bildsten

Ground-based and spacecraft telescopic observations, combined with an intensive modeling effort, have greatly enhanced our understanding of hot giant planets and brown dwarfs over the past ten years. Although these objects are all fluid,…

Earth and Planetary Astrophysics · Physics 2020-12-09 Adam P. Showman , Xianyu Tan , Vivien Parmentier

White dwarfs (WDs) are the final fate of about 97\% of the stars in our galaxy, making them vital tracers of stellar history. A fraction of WDs exist in cataclysmic variable (CV) systems, accreting matter from a nearby companion star. A…

Solar and Stellar Astrophysics · Physics 2026-03-02 Praphull Kumar , Dean M. Townsley , Hunter Anz

A significant fraction of white dwarfs harbour a magnetic field with strengths ranging from a few kG up to about 1000 MG. The fraction appears to depend on the specific class of white dwarfs being investigated and may hold some clues to the…

Solar and Stellar Astrophysics · Physics 2018-01-18 A. Kawka

We have conducted a spectroscopic survey of over 1300 bright (V < 17.5), hydrogen-rich white dwarfs based largely on the last published version of the McCook & Sion catalog. The complete results from our survey, including the spectroscopic…

Solar and Stellar Astrophysics · Physics 2015-05-30 Alexandros Gianninas , Pierre Bergeron , Maria Teresa Ruiz