183 citations · 2k across the 70 of their papers we have counts for
12 papers · 1 filter
On the Spectral Evolution of Hot White Dwarf Stars. II. Time-dependent Simulations of Element Transport in Evolving White Dwarfs with STELUM
A. Bédard, P. Brassard, P. Bergeron +1
White dwarf stars are subject to various element transport mechanisms that can cause their surface composition to change radically as they cool, a phenomenon known as spectral evol…
No evidence for a strong decrease of planetesimal accretion in old white dwarfs
Simon Blouin, Siyi Xu
A large fraction of white dwarfs are accreting or have recently accreted rocky material from their planetary systems, thereby polluting their atmospheres with elements heavier than…
Gemini/GMOS Transmission Spectroscopy of the Grazing Planet Candidate WD 1856+534 b
Siyi Xu, Hannah Diamond-Lowe, Ryan J. MacDonald +12
WD 1856+534 b is a Jupiter-sized, cool giant planet candidate transiting the white dwarf WD 1856+534. Here, we report an optical transmission spectrum of WD 1856+534 b obtained fro…
The SNIa Runaway LP 398-9: Detection of Circumstellar Material and Surface Rotation
Vedant Chandra, Hsiang-Chih Hwang, Nadia L. Zakamska +12
A promising progenitor scenario for Type Ia supernovae (SNeIa) is the thermonuclear detonation of a white dwarf in a close binary system with another white dwarf. After the primary…
Hot Degenerates in the MCT Survey. III. A Sample of White Dwarf Stars in the Southern Hemisphere
P. Bergeron, F. Wesemael, G. Fontaine +7
We present optical spectra of 144 white dwarfs detected in the Montreal-Cambridge-Tololo (MCT) colorimetric survey, including 120 DA, 12 DB, 4 DO, 1 DQ, and 7 DC stars. We also per…
Phase Separation in Ultramassive White Dwarfs
Simon Blouin, Jerome Daligault
Ultramassive white dwarfs are extreme endpoints of stellar evolution. Recent findings, such as a missing multi-Gyr cooling delay for a number of ultramassive white dwarfs and a whi…
Recurring Planetary Debris Transits and Circumstellar Gas around White Dwarf ZTF J03281219
Zachary P. Vanderbosch, Saul Rappaport, Joseph A. Guidry +14
We present follow-up photometry and spectroscopy of ZTF J03281219 strengthening its status as a white dwarf exhibiting transiting planetary debris. Using TESS and Zwicky Transie…
Direct Evaluation of the Phase Diagrams of Dense Multicomponent Plasmas by Integration of the Clapeyron Equations
Simon Blouin, Jerome Daligault
Accurate phase diagrams of multicomponent plasmas are required for the modeling of dense stellar plasmas, such as those found in the cores of white dwarf stars and the crusts of ne…
Ne Phase Separation As A Solution To The Ultramassive White Dwarf Cooling Anomaly
Simon Blouin, Jerome Daligault, Didier Saumon
The precise astrometric measurements of the Gaia Data Release 2 have opened the door to detailed tests of the predictions of white dwarf cooling models. Significant discrepancies b…
The Most Massive White Dwarfs in the Solar Neighborhood
Mukremin Kilic, P. Bergeron, Simon Blouin +1
We present an analysis of the most massive white dwarf candidates in the Montreal White Dwarf Database 100 pc sample. We identify 25 objects that would be more massive than $1.3~M_…
Bayesian constraints on the origin and geology of exo-planetary material using a population of externally polluted white dwarfs
John H. D. Harrison, Amy Bonsor, Mihkel Kama +3
White dwarfs that have accreted planetary bodies are a powerful probe of the bulk composition of exoplanetary material. In this paper, we present a Bayesian model to explain the ab…
Discovery of Beryllium in White Dwarfs Polluted by Planetesimal Accretion
Beth Klein, Alexandra E. Doyle, B. Zuckerman +5
The element beryllium is detected for the first time in white dwarf stars. This discovery in the spectra of two helium-atmosphere white dwarfs was made possible only because of the…