相关论文: Cool white dwarfs : cooling theory and Galactic im…
We present new white dwarf evolutionary sequences for low-metallicity progenitors. White dwarf sequences have been derived from full evolutionary calculations that take into account the entire history of progenitor stars, including the…
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…
We present a detailed calculation of model atmospheres for DA white dwarfs. Our atmosphere code solves the atmosphere structure in local thermodynamic equilibrium with a standard partial linearization technique, which takes into account the…
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…
By comparing two age indicators of high-mass white dwarfs derived from Gaia data, two discoveries have been made recently: one is the existence of a cooling anomaly that produces the Q branch structure on the Hertzsprung--Russell diagram,…
Approximately $0.2 \pm 0.2$ of white dwarfs (WDs) show signs of pollution by metals, which is likely due to the accretion of tidally disrupted planetary material. Models invoking planet-planet interactions after WD formation generally…
We present an improved treatment for the scattering of heavy dark matter from the ion constituents of a white dwarf. In the heavy dark matter regime, multiple collisions are required for the dark matter to become gravitationally captured.…
Studies of cool white dwarfs in the solar neighbourhood have placed a limit on the age of the Galactic disk of 8-9 billion years. However, determining their cooling ages requires the knowledge of their effective temperatures, masses, radii,…
Once carbon--oxygen white dwarfs cool sufficiently, they crystallize from the inside out. If the white dwarf is rich enough in ${}^{22}\mathrm{Ne}$, these crystallized solids are buoyant and rapidly rise, efficiently liberating potential…
Quantum corrections can be important for diffusion and the melting temperature of dense plasmas in compact astrophysical objects, particulary white dwarfs and neutron stars. Typically ions in these systems are modeled classically, but…
The white dwarf luminosity function is well understood in terms of standard model physics and leaves little room for exotic cooling mechanisms related to the possible existence of new weakly interacting light particles. This puts…
The 3-body crystallization diagrams of C/O/Ne ionic mixtures characteristic of white dwarf interiors are examined within the framework of the density-functional theory of freezing. The crystallization process is described more accurately…
This document presents a numerical study of the effects of high density nuclear reactions, pycnonuclear reactions, on the evolution of white dwarfs that accrete matter from a companion star. Primarily we seek observable properties that…
Currently there are two main techniques for independently determining the ages of stellar populations: main sequence evolution theory (via cluster isochrones) and white dwarf cooling theory. Open clusters provide the ideal environment for…
Motivated by the possibility that the fundamental ``constants'' of nature could vary with time, this paper considers the long term evolution of white dwarf stars under the combined action of proton decay and variations in the gravitational…
NGC 6791 is a well-studied, metal-rich open cluster that is so close to us that can be imaged down to luminosities fainter than that of the termination of its white dwarf cooling sequence, thus allowing for an in-depth study of its white…
The recent discovery of microlensing of stars in the Large Magellanic Cloud has excited much interest in the nature of the lensing population. Detailed analyses indicate that the mass of these objects ranges from 0.3-0.8 solar masses,…
We analysed the cooling of white dwarfs in the globular cluster 47 Tucanae using deep observations from the Hubble Space Telescope that resolve the white dwarf cooling sequence to late enough cooling times that the white dwarf core has…
The present infrared brightness of a planet originates partly from the accretion energy that the planet gained during its formation and hence provides important constraints to the planet formation process. A planet cools down from a hot…
Recently, a new class of white dwarfs (``slowly cooling WDs'') has been identified in the globular cluster M13. The cooling time of these stars is increased by stable thermonuclear hydrogen burning in their residual envelope. These WDs are…