Related papers: White dwarf binaries suggest a common envelope eff…
Establishing a large sample of post common envelope binaries (PCEBs) that consist of a white dwarf plus an intermediate mass companion star of spectral type AFGK, offers the potential to provide new constraints on theoretical models of…
We construct evolutionary models of the remnant of the merger of two carbon-oxygen (CO) core white dwarfs (WDs). With total masses in the range $1-2 {\rm M_\odot}$, these remnants may either leave behind a single massive WD or undergo a…
Detached white dwarf + main sequence (WD+MS) systems represent the simplest population of post-common envelope binaries (PCEBs). Since the ensemble properties of this population carries important information about the characteristics of the…
Post-common-envelope binaries (PCEBs) have been frequently used to observationally constrain models of close-compact-binary evolution, in particular common-envelope (CE) evolution. However, recent surveys have detected PCEBs consisting of a…
Helium accretion induced explosions in CO white dwarfs (WDs) are considered promising candidates for a number of observed types of stellar transients, including supernovae (SNe) of Type Ia and Type Iax. However, a clear favorite outcome has…
White dwarf (WD) stars evolve simply and predictably, making them reliable age indicators. However, self-consistent validation of the methods for determining WD total ages has yet to be widely performed. This work uses 1565 wide ( > 100 au)…
Ultra-massive white dwarfs ($\rm M_{WD} \gtrsim 1.05\, M_{\odot}$) are considered powerful tools to study type Ia supernovae explosions, merger events, the occurrence of physical processes in the Super Asymptotic Giant Branch (SAGB) phase,…
Massive stars are usually found in binaries, and binaries with periods less than 10 days may have a preference for near equal component masses. In this paper we investigate the evolution of these binaries all the way to contact and the…
We describe the evolution of double degenerate binary systems, consisting of components obeying the zero temperature mass radius relationship for white dwarf stars, from the onset of mass transfer to one of several possible outcomes…
Ultra-massive white dwarfs (UMWDs) with masses larger than 1.05Msun are basically believed to harbour oxygen-neon (ONe) cores. Recently, Gaia data reveals an enhancement of UMWDs on Hertzsprung-Russell diagram (HRD), which indicates that…
We evolve stellar models to study the common envelope (CE) interaction of an early asymptotic giant branch star of initial mass $5\,\rm M_{\odot}$ with a companion star of mass ranging from $0.1$ to $2\,\rm M_{\odot}$. We model the CE as a…
We present a method for modeling the evolution of detached double white dwarf (DWD) binaries hosting helium donors from the end of the common envelope (CE) phase to the onset of Roche Lobe overflow (RLOF). This is achieved by combining…
Context. Understanding the survival and orbital evolution of brown dwarf (BD) companions during the post-main-sequence (MS) evolution of their host stars is increasingly important, especially with recent discoveries of many substellar…
The unique core-mass - radius relation for giants with degenerate helium cores enables us to reconstruct the evolution of three observed double helium white dwarfs with known masses of both components. The last mass transfer phase in their…
White dwarfs (WDs) are believed to detonate via explosive Carbon-fusion in a Type Ia Supernova when their temperature and/or density reach the point where Carbon is ignited in a runaway reaction. Observations of the Type Ia supernova (SN)…
I demonstrate that an effect similar to the Roemer delay, familiar from timing radio pulsars, should be detectable in the first eclipsing double white dwarf (WD) binary, NLTT 11748. By measuring the difference of the time between the…
We present a detailed analysis of 101 white dwarf-main sequence binaries (WDMS) from the Sloan Digital Sky Survey (SDSS) for which multiple SDSS spectra are available. We detect significant radial velocity variations in 18 WDMS, identifying…
Double white dwarf (DWD) binaries are natural outcomes of binary stellar evolution and key sources for future space-based gravitational wave (GW) observatories such as Laser Interferometer Space Antenna (LISA). We investigate how different…
Evolution of a large part of low-mass X-ray binaries (LMXBs) leads to the formation of rapidly rotating pulsars with a helium white dwarf (He WD) companion. Observations indicate that some He WDs in binary pulsar systems are ultracool (with…
We propose a common envelope evolution (CEE) scenario where a red giant branch (RGB) star engulfs a planet during its core helium flash to explain the puzzling system WD 1856+534 where a planet orbits a white dwarf (WD) of mass 0.52Mo with…