Related papers: Evolution of Cool Close Binaries - Approach to Con…
A binary in which a slightly evolved star starts mass transfer to a neutron star can evolve towards ultra-short orbital periods under the influence of magnetic braking. This is called magnetic capture. We investigate in detail for which…
We present in this contribution our set of multiwavelength synthesis models including the evolution of single and binary stars. The main results we have obtained can be summarized as follows: (a) massive close-binary systems will start to…
Liberal evolution of interacting binaries has been proposed previously by several authors in order to meet various observed binary characteristics better than conservative evolution does. Since Algols are eclipsing binaries the distribution…
Joint statistics of periods and mass ratios of close binaries and its dependence on primary mass can be explained by assuming that seed binary companions are formed by disc fragmentation at random intervals during assemblage of stellar mass…
We determine the possible masses and radii of the progenitors of white dwarfs in binaries from fits to detailed stellar evolution models and use these to reconstruct the mass-transfer phase in which the white dwarf was formed. We confirm…
In this work, we investigate the dynamical effects of a sequence of close encounters over 200 Myr varying in the interval of 10000 -- 100000 au between a binary star system and passing stars with masses ranging from 0.1$M_{\odot}$ to…
We describe a new code to simulate the stellar evolution of a close interacting binary system. It is then used to calculate the evolution of a classical nova system composed of a 1.25 Msun Main-Sequence (MS) star and a 1.0 Msun white dwarf…
We analyze 221 eclipsing binaries (EBs) in the Large Magellanic Cloud with B-type main-sequence (MS) primaries ($M_1$ $\approx$ 4 - 14 M$_{\odot}$) and orbital periods $P$ = 20 - 50 days that were photometrically monitored by the Optical…
We present HST/WFPC2 observations of a sample of 134 ultra-cool objects (spectral types later than M7) coming from the DENIS, 2MASS and SDSS surveys, with distances estimated to range from 7 pc to 105 pc. Fifteen new ultra-cool binary…
The structure and evolution of close binary stars has been studied using the two-dimensional (2D) stellar structure algorithm developed by Deupree (1995). We have calculated a series of solar composition stellar evolution sequences of…
Almost all massive stars have bound stellar companions, existing in binaries or higher-order multiples. While binarity is theorized to be an essential feature of how massive stars form, essentially all information about such properties is…
The origin of very low-mass hydrogen-burning stars, brown dwarfs, and planetary-mass objects at the low-mass end of the initial mass function is not yet fully understood. Gravitational fragmentation of circumstellar discs provides a…
We carried out a spectroscopic investigation of single lined white dwarfs (WDs) in double degenerate (DD) systems and discuss their binary evolution. Simulated spectra of the Halpha region are used to derive upper limits on the temperature…
II UMa is a late F-type (F5) contact binary with a close-in tertiary and a distant visual companion. According to the four-color ($B$ $V$ $R_c$ $I_c$) light curves' solutions of II UMa, it is a high fill-out (f=$86.6\,\%$) and low mass…
We discuss the evolution of binaries with moderately high masses (about 10 - 30 solar masses), and with periods of about 3 - 300d, corresponding mostly to early Case B. These are usually thought to evolve either by reasonably conservative…
A binary in which a slightly evolved star starts mass transfer to a neutron star can evolve towards ultra-short orbital periods under the influence of magnetic braking. This is called magnetic capture. We investigate in detail for which…
W UMi is a near contact, semi-detached, double-lined eclipsing binary star with an orbital period of 1.7 days. Simultaneous analysis of new BVR multi-color light curves and radial velocity data yields the main astrophysical parameters of…
The evolution of a protostellar binary system is investigated while it is embedded in its parent molecular cloud core and acted upon by gas drag due to dynamical friction. Approximate analytical results are obtained for the energy and…
Short-period binary star systems dissipate orbital energy through tidal interactions that lead to tighter, more circular orbits. When at least one star in a binary has evolved off of the main sequence, orbital circularization occurs for…
Contact binary star systems represent the long-lived penultimate phase of binary evolution. Population statistics of their physical parameters inform understanding of binary evolutionary pathways and end products. We use light curves and…