Related papers: Post-common-envelope binaries from SDSS. IX: Const…
Common-envelope phases are decisive for the evolution of many binary systems. Of particular interest are cases with asymptotic giant branch (AGB) primary stars, because they are thought to be progenitors of various astrophysical transients.…
Common envelope (CE) is an important phase in the evolution of many binary systems. Giant star / compact object interaction in binaries plays an important role in high-energy phenomena as well as in the evolution of their environment.…
A common envelope (CE) is proposed as the origin of the early postoutburst spectra of many novae. A simple model is proposed to explain the properties of the CE based on the emission line strengths and an assumed density distribution. Rapid…
Over forty years of research suggests that the common envelope phase, in which an evolved star engulfs its companion upon expansion, is the critical evolutionary stage forming short-period, compact-object binary systems, such as coalescing…
Eclipsing close double white dwarf (WD) systems provide a unique opportunity to directly constrain hydrogen-envelope retention and test common-envelope (CE) evolution in low-mass stars, since they allow precise determinations of stellar…
Common-envelope evolution (CEE) is one of the biggest open questions in binary stellar evolution, despite being the main channel for the formation of close binaries. One of the main reasons CEE is difficult to model is the lack of direct…
The common envelope (CE) phase is an important stage in binary stellar evolution. It is needed to explain many close binary stellar systems, such as cataclysmic variables, Type Ia supernova progenitors, or X-ray binaries. To form the…
We calculate the outward energy transport time by convection and photon diffusion in an inflated common envelope and find this time to be shorter than the envelope expansion time. We conclude therefore that most of the hydrogen…
Massive star evolution plays a crucial role in astrophysics but bares large uncertainties. This problem becomes more severe by the majority of massive stars being born in close binary systems, whose evolution is affected by the interaction…
Any variation of the fundamental physical constants, and more particularly of the fine structure constant, $\alpha$, or of the mass of the electron, $m_e$, would affect the recombination history of the Universe and cause an imprint on the…
As part of a larger program aimed at better quantifying the uncertainties in stellar computations, we attempt to calibrate the extent of convective overshooting in low to intermediate mass stars by means of eclipsing binary systems. We…
In some extensions of the standard model of particle physics, the values of the fundamental coupling constants vary in space and time. Some observations of quasars hint at time and spatial variation of the fine structure constant $\alpha$.…
The dynamical method provides an efficient way to discover post-common-envelope binaries (PCEB) with faint white dwarfs (WDs), thanks to the development of time-domain survey projects. We perform a comprehensive analysis of the PCEB system…
Common envelopes are thought to be the main method for producing tight binaries in the universe as the orbital period shrinks by several orders of magnitude during this phase. Despite their importance for various evolutionary channels,…
The morphology of planetary nebulae emerging from the common envelope phase of binary star evolution is investigated. Using initial conditions based on the numerical results of hydrodynamical simulations of the common envelope phase it is…
Compact binary systems emitting gravitational waves (GWs) can exhibit orbital eccentricity, along with generic spin orientations, leading to the precession of the orbital angular momentum, individual spins, and the orbital plane. While…
This paper presents the constraints on the time variation of the fine structure constant at recombination relative to its present value, Delta_alpha = (alpha_rec-alpha_0) / alpha_0, obtained from the analysis of the WMAP-3yr Cosmic…
We discuss present and future cosmological constraints on variations of the fine structure constant $\alpha$ induced by an early dark energy component having the simplest allowed (linear) coupling to electromagnetism. We find that current…
Compact binary systems coalesce over time due to the radiation of gravitational waves, following the field equations of general relativity. Conservation of energy and angular momentum gives a mathematical description for the evolution of…
We examine cosmic microwave background constraints on variations in the recombination history of the universe. We use a very general extension to the standard model of recombination characterized by two parameters, a and b, which multiply…