Related papers: An Apparent Precessing Helical Outflow from a Mass…
Some binary stars experience common envelope evolution, which is accompanied by drastic loss of angular momentum, mass, and orbital energy and which leaves behind close binaries often involving at least one white dwarf, neutron star, or…
We model the late evolution and mass loss history of rapidly rotating Wolf-Rayet stars in the mass range $5\,\rm{M}_{\odot}\dots 100\,\rm{M}_{\odot}$. We find that quasi-chemically homogeneously evolving single stars computed with enhanced…
Virtually all binaries consisting of a white dwarf with a non-degenerate companion can be classified as either close post-interaction systems (with orbital periods of a few days or less), or wide systems (with periods longer than decades),…
Some hot, massive, population-I Wolf-Rayet (WR) stars of the carbon subclass are known to be prolific dust-producers. How dust can form in such a hostile environment remains a mystery. Here we report the discovery of a relatively cool,…
Despite their unique astrophysical relevance, the outcome of white dwarf binary mergers has so far only been studied for a very restricted number of systems. Here we present the results of a survey with more than two hundred simulations…
The high luminosity of massive, early-type stars drives strong stellar winds through line scattering of the stars continuum radiation. Their momenta contribute substantially to the dynamics and energetics of the ambient interstellar medium…
One of the main properties of Wolf-Rayet (WR) stars is a very intense outflow of gas. No less than 40\% \ of WR stars belong to binary systems. Young massive O and B stars are the secondary components of such systems. OB stars also have an…
Classical Cepheids are key probes of both stellar astrophysics and cosmology as standard candles and pulsating variable stars. It is important to understand Cepheids in unprecedented detail in preparation for upcoming GAIA, JWST and…
Recent observations of supernovae (SNe) have indicated that a fraction of massive stars possess dense circumstellar medium (CSM) at the moment of their core collapses. They suggest the presence of additional activities of the SN progenitor…
Hot subdwarf stars with masses above $0.8 M_\odot$ ascend the helium giant branch after the end of core helium burning, before entering the white dwarf cooling track or exploding as type Ib/c supernovae. Such massive helium stars are…
Supersonic winds from massive stars carry great amounts of kinetic power and modify the surrounding interstellar medium. Through this interaction a stellar bubble is formed. Theoretical studies and recent observations suggest that the winds…
Wolf-Rayet stars (WRs) are evolved massive stars in the brief stage before they undergo core collapse. Not only are they rare, but they also can be particularly difficult to find due to the high extinction in the Galactic plane. This paper…
We carry out a systematic study of the response of companion stars in massive binaries after being impacted by supernova ejecta. A total of 720 1D stellar evolution calculations are performed to follow the inflation and contraction of the…
The presence of massive O-type stars with surfaces enriched by CNO-cycle products has been known since the early 1980s. For many years, internal rotational mixing was assumed to be the dominant mechanism responsible for this chemical…
Massive colliding-wind binaries that host a Wolf-Rayet (WR) star present a potentially important source of dust and chemical enrichment in the interstellar medium (ISM). However, the chemical composition and survival of dust formed from…
WR 31a (Hen 3-519) is likely a post-luminous blue variable (LBV) star that is evolving to become a classical Wolf-Rayet star. Multicolor (UBVR) photopolarimetric observations of WR 31a were obtained over nine nights in early 2007. The…
Our understanding of massive stars remains incomplete. Many high-z galaxies and nearby analogs exhibit strong He II emission, indicating an abundance of photons with energies >54.4 eV that standard single-star population models cannot…
We present a suite of binary evolution models with massive primaries (10 $\leq$ M$_1$ $\leq$ 40 M$_\odot$) and periods and mass ratios chosen such that the systems undergo non-conservative mass transfer while the primaries have helium…
We discovered that the Wolf-Rayet (WR)+OB star binary, WR 104, renowned for its associated "dusty pinwheel nebula" recently spatially resolved with infrared interferometry, exhibits strong quasi-periodic optical variations with a full…
Stripped stars are a common product of binary stellar systems and span a wide mass range from Wolf-Rayet stars to hot subdwarfs and helium white dwarfs. The recent discovery of intermediate-mass stripped stars, with masses between those of…