Related papers: Starspots in contact and semi-detached binary syst…
Deriving the distribution of binary parameters for a particular class of stars over the full range of orbital separations usually requires the combination of results from many different observing techniques (radial velocities,…
We present spectroscopic and photometric solutions for three spotted systems with red giant components. Absolute physical and orbital parameters for these double-lined detached eclipsing binary stars are presented for the first time. These…
Tidal locking of planets to their host stars results in an atmospheric circulation with a hotspot fixed to the frame of reference of the planet. On the other hand, asynchronously rotating planets feature moving hotspots either lagging or…
Detailed atmospheric characterization of exoplanets by transmission spectroscopy requires careful consideration of stellar surface inhomogeneities induced by starspots. This effect is particularly problematic for planetary systems around…
Wide-field high precision photometric surveys such as Kepler have produced reams of data suitable for investigating stellar magnetic activity of cooler stars. Starspot activity produces quasi-sinusoidal light curves whose phase and…
Nearby companions alter the evolution of massive stars in binary systems. Using a sample of Galactic massive stars in nearby young clusters, we simultaneously measure all intrinsic binary characteristics relevant to quantify the frequency…
A number of efforts are underway to detect close binary stars in planetary nebulae. The primary goal of these studies is to determine the binary fraction of central stars. The next stage is a detailed analysis of the binaries to determine…
Be stars are rapidly rotating B type stars. The origin of their rapid rotation is not certain, but binary interaction remains to be a possibility. In this work we investigate the formation of Be stars resulting from mass transfer in…
Our discovery of 1SWASP J093010.78+533859.5 as a probable doubly eclipsing quadruple system containing a contact binary with P~0.23 d and a detached binary with P~1.31 d was announced in 2013. Subsequently Koo et al. confirmed the detached…
We discuss methods for modeling eclipsing binary stars using the "physical", "simplified" and "phenomenological" models. There are few realizations of the "physical" Wilson-Devinney (1971) code and its improvements, e.g. Binary Maker,…
In this work we present a model of two young eclipsing binaries in the Orion Complex. Both heavily spotted, they present radii and temperatures that are in disagreement with the predictions of standard stellar models. 2M05-06 consists of…
Motivated by suggestions that binaries with almost equal-mass components ("twins") play an important role in the formation of double neutron stars and may be rather abundant among binaries, we study the stability of synchronized close and…
The fundamental properties of detached eclipsing binary stars can be measured very accurately, which could make them important objects for constraining the treatment of convection in theoretical stellar models. However, only four or five…
The recent sample of 21 detached eclipsing binaries in the Small Magellanic Cloud (Harries et al. 2003, Hilditch et al. 2005) provides a valuable test of the binary mass function for massive stars. We show that 50% of detached binaries have…
ASAS is a long term project to monitor bright variable stars over the whole sky. It has discovered 50,122 variables brighter than V < 14 mag south of declination +28 degrees, and among them 11,099 eclipsing binaries. We present a…
Individual components of well-detached binary systems are assumed to be two single-like stars with a common origin, i.e. they share the same chemical composition and same age. Therefore, one expects to fit the observed parameters of both…
We examine the possibility that very massive stars greatly exceeding the commonly adopted stellar mass limit of 150 Msun may be present in young star clusters in the local universe. We identify ten candidate clusters, some of which may host…
We present a model for the formation of high-mass close binary systems in the context of forming massive stars through gas accretion in the centres of stellar clusters. A low-mass wide binary evolves under mass accretion towards a high-mass…
Binary stars and higher-order multiple systems are an ubiquitous outcome of star formation, especially as the system mass increases. The companion mass-ratio distribution is a unique probe into the conditions of the collapsing cloud core…
Despite being the most abundant (by space density) of interacting binary stars, W Ursae Majoris (W UMa) stars are not understood structurally. Their stellar components are in physical contact, and share a common convective envelope.…