Results 101 to 110 of about 1,877,533 (362)

White Dwarf Crystallization [PDF]

open access: yesInternational Astronomical Union Colloquium, 1994
AbstractThe inclusion of a detailed treatment of solidification processes in the cooling theory of carbon–oxygen white dwarfs is of crucial importance for the determination of their luminosity function. Carbon–oxygen separation at crystallization yields delays larger than 2 Gyr to cool down to luminosities corresponding to the observed cut–off.
Enrique García-Berro, M. Hernanz
openaire   +2 more sources

An irradiated brown-dwarf companion to an accreting white dwarf [PDF]

open access: yesNature, 2016
Brown dwarfs and giant planets orbiting close to a host star are subjected to significant irradiation that can modify the properties of their atmospheres. In order to test the atmospheric models that are used to describe these systems, it is necessary to obtain accurate observational estimates of their physical properties (masses, radii, temperatures ...
S. P. Littlefair   +10 more
openaire   +9 more sources

Resistance Drift of Phase Change Materials Beyond the Power Law

open access: yesAdvanced Electronic Materials, EarlyView.
The timedependent resistance of phase change materials is important for their application as electronic memory. Here, resistance measurements of melt‐quenched germanium telluride from nanoseconds to minutes are presented. By going far beyond the usually considered measurement regime, deviations from the ubiquitous power law behavior are observed, that ...
Jakob Ballmaier   +2 more
wiley   +1 more source

The 100 pc White Dwarf Sample in the SDSS Footprint. II. A New Look at the Spectral Evolution of White Dwarfs

open access: yesThe Astrophysical Journal
We increase the spectroscopic completeness of the 100 pc white dwarf sample in the Sloan Digital Sky Survey footprint with 840 additional spectra. Our spectroscopy is 86% complete for white dwarfs hotter than T _eff  = 5000 K, where H α remains visible ...
Mukremin Kilic   +7 more
doaj   +1 more source

The Halo White Dwarf Population [PDF]

open access: yesThe Astrophysical Journal, 1998
29 pages (AASTeX), 7 eps figures included, accepted for publication in ...
Enrique García-Berro   +4 more
openaire   +3 more sources

Absolute Proper Motions to B~22.5: IV. Faint, Low Velocity White Dwarfs and the White Dwarf Population Density Law [PDF]

open access: yes, 2001
The reduced proper motion diagram (RPMD) for a complete sample of faint stars with high accuracy proper motions in the North Galactic Pole field SA57 is investigated. Eight stars with very large reduced proper motions are identified as faint white dwarf candidates.
arxiv   +1 more source

The Insistence of Blackness and the Persistence of Antiblackness in Ireland

open access: yesAustralian Journal of Social Issues, EarlyView.
ABSTRACT This paper positions Ireland as a critical site for examining the insistence of blackness and an antiblackness created and sustained through Irish ethnonationalist imaginaries and exclusionary processes. Drawing on connected sociologies and Irish Black Studies, this enquiry argues that antiblackness in Ireland operates as a generational force,
Philomena Mullen
wiley   +1 more source

Novel Atmospheric Dynamics Shape the Inner Edge of the Habitable Zone around White Dwarfs

open access: yesThe Astrophysical Journal
White dwarfs offer a unique opportunity to search nearby stellar systems for signs of life, but the habitable zone around these stars is still poorly understood.
Ruizhi Zhan   +2 more
doaj   +1 more source

A Chondritic Solar Neighborhood

open access: yesThe Planetary Science Journal, 2023
A persistent question in exoplanet demographics is whether exoplanetary systems form from similar compositional building blocks to our own. Polluted white dwarf stars offer a unique way to address this question, as they provide measurements of the bulk ...
Isabella L. Trierweiler   +2 more
doaj   +1 more source

Presupernova evolution of accreting white dwarfs with rotation [PDF]

open access: yesAstron.Astrophys. 419 (2004) 623, 2004
We discuss the effects of rotation on the evolution of accreting carbon-oxygen white dwarfs, with the emphasis on possible consequences in Type Ia supernova (SN Ia) progenitors. Starting with a slowly rotating white dwarf, we simulate the accretion of matter and angular momentum from a quasi-Keplerian accretion disk.
arxiv   +1 more source

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