424 citations · 3k across the 35 of their papers we have counts for
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A hidden population of white dwarfs with atmospheric carbon traces in the Gaia bifurcation
Maria Camisassa, Santiago Torres, Mark Hollands +4
The ESA Gaia space mission has revealed a bifurcation of the white dwarf (WD) sequence on the color magnitude diagram in two branches: A and B. While the A branch consists mostly o…
Two decades of optical timing of the shortest-period binary star system HM Cancri
James Munday, T. R. Marsh, Mark Hollands +15
The shortest-period binary star system known to date, RX J0806.3+1527 (HM Cancri), has now been observed in the optical for more than two decades. Although it is thought to be a do…
white dwarfs within 40 pc III: spectroscopic observations of new candidates in the southern hemisphere
Mairi W. O'Brien, P. -E. Tremblay, N. P. Gentile Fusillo +31
We present a spectroscopic survey of 248 white dwarf candidates within 40 pc of the Sun; of these 244 are in the southern hemisphere. Observations were performed mostly with the Ve…
Spectral analysis of ultra-cool white dwarfs polluted by planetary debris
Abbigail K. Elms, Pier-Emmanuel Tremblay, Boris T. Gänsicke +5
We identify two ultra-cool ( K) metal-polluted (DZ) white dwarfs WDJ21474035 and WDJ19220233 as the coolest and second coolest DZ stars known to date w…
A catalogue of white dwarfs in Gaia EDR3
N. P. Gentile Fusillo, P. -E. Tremblay, E. Cukanovaite +7
We present a catalogue of white dwarf candidates selected from Gaia early data release three (EDR3). We applied several selection criteria in absolute magnitude, colour, and Gaia q…
Constraining the solar neighbourhood age-metallicity relation from white dwarf-main sequence binaries
A. Rebassa-Mansergas, J. Maldonado, R. Raddi +11
The age-metallicity relation is a fundamental tool for constraining the chemical evolution of the Galactic disc. In this work we analyse the observational properties of this relati…
8.9-hr Rotation in the Partly Burnt Runaway Stellar Remnant LP 40-365 (GD 492)
J. J. Hermes, Odelia Putterman, Mark A. Hollands +5
We report the detection of 8.914-hr variability in both optical and ultraviolet light curves of LP 40-365 (also known as GD 492), the prototype for a class of partly burnt runaway…
White dwarfs with planetary remnants in the era of Gaia I: six emission line systems
N. P. Gentile Fusillo, C. J. Manser, Boris T. Gänsicke +17
White dwarfs with emission lines from gaseous debris discs are among the rarest examples of planetary remnant hosts, but at the same time they are key objects for studying the fina…
white dwarfs within 40 pc II: the volume-limited northern hemisphere sample
Jack McCleery, Pier-Emmanuel Tremblay, Nicola Pietro Gentile Fusillo +6
We present an overview of the sample of northern hemisphere white dwarfs within 40 pc of the Sun detected from Data Release 2 (DR2). We find that 521 sources are spectroscop…
white dwarfs within 40 pc I: spectroscopic observations of new candidates
P. -E. Tremblay, M. A. Hollands, N. P. Gentile Fusillo +30
We present a spectroscopic survey of 230 white dwarf candidates within 40 pc of the Sun from the William Herschel Telescope and Gran Telescopio Canarias. All candidates were select…
An ultra-massive white dwarf with a mixed hydrogen-carbon atmosphere as a likely merger remnant
Mark A. Hollands, Pier-Emmanuel Tremblay, Boris T. Gänsicke +11
White dwarfs are dense, cooling stellar embers consisting mostly of carbon and oxygen, or oxygen and neon (with a few percent carbon) at higher initial stellar masses. These stella…
From Hydrogen to Helium: The Spectral Evolution of White Dwarfs as Evidence for Convective Mixing
Tim Cunningham, Pier-Emmanuel Tremblay, Nicola Pietro Gentile Fusillo +2
We present a study of the hypothesis that white dwarfs undergo a spectral change from hydrogen- to helium-dominated atmospheres using a volume-limited photometric sample drawn from…
Core crystallization and pile-up in the cooling sequence of evolving white dwarfs
Pier-Emmanuel Tremblay, Gilles Fontaine, Nicola Pietro Gentile Fusillo +7
White dwarfs are stellar embers depleted of nuclear energy sources that cool over billions of years. These stars, which are supported by electron degeneracy pressure, reach densiti…
A Volume Limited Sample of Cataclysmic Variables from DR2: Space Density and Population Properties
A. F. Pala, B. T. Gänsicke, E. Breedt +15
We present the first volume-limited sample of cataclysmic variables (CVs), selected using the accurate parallaxes provided by the second data release (DR2) of the ESA $\mathit{Gaia…
Partly burnt runaway stellar remnants from peculiar thermonuclear supernovae
R. Raddi, M. A. Hollands, D. Koester +13
We report the discovery of three stars that, along with the prototype LP40-365, form a distinct class of chemically peculiar runaway stars that are the survivors of thermonuclear e…
Fundamental parameter accuracy of DA and DB white dwarfs in Gaia Data Release 2
P. -E. Tremblay, E. Cukanovaite, N. P. Gentile Fusillo +2
We report on a comparison of spectroscopic analyses for hydrogen (DA) and helium atmosphere (DB) white dwarfs with Gaia Data Release 2 (DR2) parallaxes and photometry. We assume a…
A Data Release 2 catalogue of white dwarfs and a comparison with SDSS
Nicola Pietro Gentile Fusillo, Pier-Emmanuel Tremblay, Boris T. Gänsicke +11
We present a catalogue of white dwarf candidates selected from the second data release of (DR2). We used a sample of spectroscopically confirmed white dwarfs from the Sloan…
The Gaia 20 pc white dwarf sample
M. A. Hollands, P. E. Tremblay, B. T. Gaensicke +2
Using Gaia DR2 data, we present an up-to-date sample of white dwarfs within 20 pc of the Sun. In total we identified 139 systems in Gaia DR2, nine of which are new detections, with…
Anatomy of the hyper-runaway star LP 40-365 with Gaia
R. Raddi, M. A. Hollands, B. T. Gaensicke +4
LP 40-365 (aka GD 492) is a nearby low-luminosity hyper-runaway star with an extremely unusual atmospheric composition, which has been proposed as the remnant of a white dwarf that…
Further insight on the hypervelocity white dwarf, LP 40-365 (GD 492): a nearby emissary from a single-degenerate Type Ia supernova
R. Raddi, M. A. Hollands, D. Koester +4
The recently discovered hypervelocity white dwarf LP 40-65 (aka GD 492) has been suggested as the outcome of the failed disruption of a white dwarf in a sub-luminous Type Ia supern…
Cool DZ white dwarfs II: Compositions and evolution of old remnant planetary systems
Mark Hollands, Boris Gaensicke, Detlev Koester
In a previous study, we analysed the spectra of 230 cool ( < 9000 K) white dwarfs exhibiting strong metal contamination, measuring abundances for Ca, Mg, Fe and in…
The white dwarf binary pathways survey - II. Radial velocities of 1453 FGK stars with white dwarf companions from LAMOST DR4
A. Rebassa-Mansergas, J. J. Ren, P. Irawati +18
We present the second paper of a series of publications aiming at obtaining a better understanding regarding the nature of type Ia supernovae (SNIa) progenitors by studying a large…
Multi-band photometry and spectroscopy of an all-sky sample of bright white dwarfs
R. Raddi, N. P. Gentile Fusillo, A. F. Pala +11
The upcoming NASA Transiting Exoplanet Survey Satellite (TESS) will obtain space-based uninterrupted light curves for a large sample of bright white dwarfs distributed across the e…
Cool DZ white dwarfs I: Identification and spectral analysis
Mark Hollands, Detlev Koester, Vadim Alekseev +2
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 ide…