Related papers: Low and intermediate-mass close binary evolution a…

Since close WR+O binaries are the result of a strong interaction of both stars in massive close binary systems, they can be used to constrain the highly uncertain mass and angular momentum budget during the major mass transfer phase. We…

We have revisited the sdB+K-star long-period binary PG 1018-047 based on 20 new high-resolution VLT/UVES spectra that provided regular coverage over a period of more than 26 months. We refine the period and establish that the orbit is…

Abridged: We have undertaken a series of hydrodynamical simulations of multiple star formation in small turbulent molecular clouds. Our goal is to determine the sensitivity of the properties of the resulting stars and brown dwarfs to…

The first stars might have been fast rotators. This would have important consequences for their radiative, mechanical and chemical feedback. We discuss the impact of fast initial rotation on the evolution of massive Population III models…

Convective core overshooting extends the main-sequence lifetime of a star. Evolutionary tracks computed with overshooting are quite different from those that use the classical Schwarzschild criterion, which leads to rather different…

Today, Type Ia supernovae are essential tools for cosmology, and recognized as major contributors to the chemical evolution of galaxies. The construction of detailed supernova progenitor models, however, was so far prevented by various…

HD 213597 is an eclipsing binary system which was detected by the STEREO spacecraft and was speculated to host a low-mass stellar companion. We used high-resolution spectroscopy with the 10-m Hobby-Eberly Telescope and the 1.2-m telescope…

A number of recent studies have proposed that the stellar initial mass function (IMF) of early type galaxies varies systematically as a function of galaxy mass, with higher mass galaxies having bottom heavy IMFs. These bottom heavy IMFs…

Binaries in double-lined spectroscopic systems provide a homogeneous set of stars. Differences of parameters, such as age or initial conditions, which otherwise would have strong impact on the stellar evolution, can be neglected. The…

We report the discovery of three edge-on binaries with white dwarf companions that gravitationally magnify (instead of eclipsing) the light of their stellar primaries, as revealed by a systematic search for pulses with long periods in the…

We use the ZFIRE survey (http://zfire.swinburne.edu.au) to investigate the high mass slope of the initial mass function (IMF) for a mass-complete (log10(M$_*$/M$_\odot$)~9.3) sample of 102 star-forming galaxies at z~2 using their H$\alpha$…

The first generation of stars was formed from primordial gas. Numerical simulations suggest that the first stars were predominantly very massive, with typical masses M > 100 Mo. These stars were responsible for the reionization of the…

Theoretical arguments and indirect observational evidence suggest that the stellar initial mass function (IMF) may evolve with time, such that it is more weighted toward high mass stars at higher redshift. Here we test this idea by…

2MASS J03202839-0446358AB is a recently identified, late-type M dwarf/T dwarf spectroscopic binary system for which both the radial velocity orbit for the primary and spectral types for both components have been determined. By combining…

We present the preliminary results of a survey of the open clusters NGC3532 and NGC2287 for new white dwarf members which can help improve understanding of the form of the upper end of the stellar initial mass-final mass relation. We…

I present a new Galactic chemical evolution model motivated by and grounded in the hierarchical theory of galaxy formation, as expressed by a halo merger history of the Galaxy. This model accurately reproduces the "metallicity distribution…

Using self-consistent chemodynamical simulations including star formation, supernova feedback, and chemical enrichment, I show the dependence of cosmic star formation and chemical enrichment histories on the initial mass function (IMF). The…

We employ planetary evolution modeling to reproduce the MR distribution of the 198 so far detected planets with mass and radius measured to the <45% and <15% level, respectively, and less massive than 108Me. We simultaneously account for…

Masses for 664 single-lined hot subdwarf stars identified in LAMOST were calculated by comparing synthetic fluxes from spectral energy distribution (SED) with observed fluxes from virtual observatory service. Three groups of hot subdwarf…

Extremely-low-mass white dwarfs (ELM WDs) with non-degenerate companions are believed to originate from solar-type main-sequence binaries undergoing stable Roche lobe overflow mass transfer when the ELM WD progenitor is at (or just past)…