Related papers: Cool white dwarfs : cooling theory and Galactic im…
Many white dwarfs have accreted material from their own planetary systems. These objects can be used to infer the composition of exoplanetary material and identify evidence for key geological processes. However, the white dwarf atmospheric…
Recently, the power of Gaia data has revealed an enhancement of high-mass white dwarfs (WDs) on the Hertzsprung--Russell diagram, called the Q branch. This branch is located at the high-mass end of the recently identified crystallization…
We present a spectro-photometric analysis of 2880 cool white dwarfs within 100 pc of the Sun and cooler than Teff = 10,000 K, with grizy Pan-STARRS photometry and Gaia trigonometric parallaxes available. We also supplement our data sets…
Using a new grid of models of cooling white dwarfs, we calculate isochrones and luminosity functions in the Johnson-Kron/Cousins and HST filter sets for systems containing old white dwarfs. These new models incorporate a non-grey atmosphere…
We consider the pulsational properties of white dwarf star models with temperatures appropriate for the ZZ Ceti instability strip and with masses large enough that they should be substantially crystallized. Our work is motivated by the…
The purpose of this work is to explore the evolution of helium-core white dwarf stars in a self-consistent way with the predictions of detailed non-gray model atmospheres and element diffusion. To this end, we consider helium-core white…
The interpretation of microlensing results towards the Large Magellanic Cloud (LMC) still remains controversial. White dwarfs have been proposed to explain these results and, hence, to contribute significantly to the mass budget of our…
NGC 6397 is one of the most interesting, well observed and theoretically studied globular clusters. The existing wealth of observations allows us to study the reliability of the theoretical white dwarf cooling sequences of low metallicity…
By introducing a simplified transport model of outer layers of white dwarfs we derive an analytical semi-empirical relation which constrains effective temperature-mass-radius for white dwarfs. This relation is used to classify recent data…
We describe a new survey for cool white dwarfs that supplements Sloan Digital Sky Survey photometry with USNO proper motions and follow-up spectroscopy. To date we have discovered and spectroscopically confirmed 80 new moderate temperature…
White dwarf stars have attracted considerable attention in the past 15 years as hosts for potentially habitable planets, but their low luminosity and continuous cooling are major challenges for habitability. Recently, astronomers have found…
White dwarf (WD) stars are considered cosmic laboratories to study the physics of dense plasma. Furthermore, the use of WD stars as cosmic clocks to date stellar populations and main sequence companions demands an appropriate understanding…
Do white dwarfs have inner cores made of iron? Neutron rich nuclei like $^{56}$Fe experience a net gravitational force and sediment toward the core. Using new phase diagrams and molecular dynamics simulations, we show that $^{56}$Fe should…
This chapter provides an in-depth overview of white dwarfs, the evolutionary terminus of the vast majority of stars. It discusses their discovery, their nature as degenerate objects, their connections to earlier phases of stellar evolution,…
We investigate the evolution of isolated, zero and finite temperature, massive, uniformly rotating and highly magnetized white dwarf stars under angular momentum loss driven by magnetic dipole braking. We consider the structure and thermal…
White dwarfs with metal lines in their spectra act as signposts for post-main sequence planetary systems. Searching the Sloan Digital Sky Survey (SDSS) data release 12, we have identified 231 cool (<9000 K) DZ white dwarfs with strong metal…
Thermal evolution of the central region of a $0.9 \, M_\odot$ C/O white dwarf at the initial stage of the ion mixture crystallization is studied by numerically solving the heat equation on a fine spatial and temporal grid and by including a…
We collected F606W- and F814W-band time-series data of the Sagittarius low-reddening window in the Galactic bulge with the Advanced Camera far Surveys mounted on the Hubble Space Telescope. We sampled the region approximately every two…
We determine the distribution of cooling ages of massive Gaia EDR3 white dwarfs identified with over 90% probability within 200 pc and with mass in the range 0.95-1.25 $M_\odot$. Using three sets of publicly available models, we consider…
The evolution of white dwarfs (WDs) depends crucially on thermal processes. The plasma in their core can produce neutrinos which escape from the star, thus contributing to the energy loss. While in absence of a magnetic field the main…