Related papers: When Do Stars Go BOOM?
White dwarfs (WDs) represent the final evolutionary stage of most stars, typically originating from progenitor stars with masses below approximately 8 $M_{\odot}$ to 10 $M_{\odot}$. Formation through single-star evolution generally requires…
Can a white dwarf, accreting hydrogen-rich matter from a non-degenerate companion star, ever exceed the Chandrasekhar mass and explode as a type Ia supernova? We explore the range of accretion rates that allow a white dwarf (WD) to…
When a star exhausts its nuclear fuel, it either explodes as a supernova or more quiescently becomes a white dwarf, an object about half the mass of our Sun with a radius of about that of the Earth. About one fifth of white dwarfs exhibit…
The discovery of the existence of an upper bound on the mass of a white dwarf star is considered as one of the finest of twentieth century astrophysics. On approaching this limiting mass of $1.4M_\odot$, known as the Chandrasekhar…
Is the Chandrasekhar mass limit for white dwarfs (WDs) set in stone? Not anymore -- recent observations of over-luminous, peculiar type Ia supernovae can be explained if significantly super-Chandrasekhar WDs exist as their progenitors, thus…
Using WFPC2 on the Hubble Space Telescope, we have isolated a sample of 258 white dwarfs (WDs) in the Galactic globular cluster M4. Fields at three radial distances from the cluster center were observed and sizeable WD populations were…
We have carried out a search for massive white dwarfs (WDs) in the direction of young open star clusters using the Gaia DR2 database. The aim of this survey was to provide robust data for new and previously known high-mass WDs regarding…
White dwarfs (WDs), the evolutionary endpoints of most stars, can form through both single-star and binary channels. While single-star evolutionary models enable reliable WD age estimates, binary evolution introduces interactions that can…
The discovery around the turn of the millenium of a population of very massive (M$_\star$ > 2$\times$10$^6$ M$_\odot$) compact stellar systems (CSS) with physical properties (radius, velocity dispersion, stellar mass etc.) that are…
We compare the mass distribution of central stars of planetary nebulae (CSPN) with those of their progeny, white dwarfs (WD). We use a dynamical method to measure masses with an uncertainty of 0.02 M$_\odot$. The CSPN mass distribution is…
We present a photometric and spectroscopic study of the white dwarf population of the populous, intermediate-age open cluster M35 (NGC 2168); this study expands upon our previous study of the white dwarfs in this cluster. We…
Planet frequency shows a strong positive correlation with host mass from the hydrogen-burning limit to M ~ 2Msun. No search has yet been conducted for planets of higher-mass hosts because all existing techniques are insensitive to these…
With the Keck I Low-Resolution Imaging Spectrometer we have observed nine white dwarf candidates in the very rich open cluster NGC 2099 (M37). The spectroscopy shows seven to be DA white dwarfs, one to be a DB white dwarf, and one to be a…
We have identified a candidate 1-2 x 10^5 year old luminous white dwarf in NGC 1818, a young star cluster in the Large Magellanic Cloud. This discovery strongly constrains the boundary mass M_c at which stars stop forming neutron stars and…
We report a spectroscopic search for hypervelocity white dwarfs (WDs) that are runaways from Type Ia supernovae (SNe Ia) and related thermonuclear explosions. Candidates are selected from Gaia data with high tangential velocities and blue…
Recent observations of Type Ia supernovae (SNe Ia) suggest that some of the progenitor white dwarfs (WDs) had masses up to 2.4-2.8 M_sun, highly exceeding the Chandrasekhar mass limit. We present a new single degenerate (SD) model for SN Ia…
All single stars that are born with masses up to 8.5 - 10 $M_\odot$ will end their lives as a white dwarf (WD) star. In this evolutionary stage, WDs enter the cooling sequence, where the stars radiate away their thermal energy, and are…
Recent discovery of several overluminous type Ia supernovae (SNe Ia) indicates that the explosive masses of white dwarfs may significantly exceed the canonical Chandrasekhar mass limit. Rapid differential rotation may support these massive…
A White Dwarf (WD) star and a main-sequence companion may interact through their different stellar evolution stages. This sort of binary population has historically helped us improve our understanding of binary formation and evolution…
Globular star clusters are among the first stellar populations to have formed in the Milky Way, and thus only a small sliver of their initial spectrum of stellar types are still burning hydrogen on the main-sequence today. Almost all of the…