Related papers: Dynamical Formation of Close Binaries During the P…
We present results from the first hydrodynamical star formation calculation to demonstrate that close binary stellar systems (separations $\lsim 10$ AU) need not be formed directly by fragmentation. Instead, a high frequency of close…
We present rotation periods for the solar-type primary stars in 13 close (a~< 5 AU) single-lined spectroscopic binaries with known orbital periods (P) and eccentricities (e). All binaries are members of the open clusters M35 (150Myr) and…
Massive stars are often found in multiple systems, yet how binary-star systems with very close separations ($\lesssim$ au) assemble remains unresolved. We investigate the formation and inward migration of massive-star binaries in…
We present a comparison between the rotation period distributions of solar-type single stars and primary stars in close binaries (0.1 AU ~< a ~< 5 AU) in the young (150 Myr) open cluster M35 (NGC 2168). We find that the primary stars in the…
We study the steady-state orbital distributions of giant planets migrating through the combination of the Kozai-Lidov (KL) mechanism due to a stellar companion and friction due to tides raised on the planet by the host star. We run a large…
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…
A set of 27 evolutionary models of cool close binaries was computed under the assumption that their evolution is influenced by the magnetized winds. Initial periods of 1.5, 2.0 and 2.5 d were considered. For each period three values of 1.3,…
Many close stellar binaries are accompanied by a far-away star. The "eccentric Kozai-Lidov" (EKL) mechanism can cause dramatic inclination and eccentricity fluctuations, resulting in tidal tightening of inner binaries of triple stars. We…
Tidal interactions in close binaries play a key role in the long-term rotational and orbital evolution. The distributions of circularization across open clusters (OCs) place strong observational constraints on tidal dissipation in binaries.…
Early B-type main-sequence (MS) stars (M$_1$ = 5-16 M$_{\odot}$) with closely orbiting low-mass stellar companions (q = M$_2$/M$_1$ < 0.25) can evolve to produce Type Ia supernovae, low-mass X-ray binaries, and millisecond pulsars. However,…
Many recent observational studies have concluded that planetary systems commonly exist in multiple-star systems. At least ~20%, and presumably a larger fraction of the known extrasolar planetary systems are associated with one or more…
Circularization of late-type main-sequence binaries is usually attributed to turbulent convection, while that of early-type binaries is explained by resonant excitation of g modes. We show that the latter mechanism operates in solar-type…
The typical product of the star formation process is a binary star. Binaries have provided the first dynamical measures of the masses of pre-main-sequence (PMS) stars, providing support for the calibrations of PMS evolutionary tracks.…
A viable solution to the origin of close binary systems, unaccounted for in recent theories, is presented. Fragmentation, occurring at the end of the secondary collapse phase (during which molecular hydrogen is dissociating), can form…
We present an ongoing study on tidal interactions in late-type close binary stars. New results on tidal circularization are combined with existing data to test and constrain theoretical predictions of tidal circularization in the…
We present the results of a study performed with the goal to investigate whether low-mass pre-main sequence binary stars are formed by multiple fragmentation or via stellar capture. If binaries form preferentially by fragmentation, we…
The initial distribution of rotational velocities of stars is still poorly known, and how the stellar spin evolves from birth to the various end points of stellar evolution is an actively debated topic. Binary interactions are often invoked…
The surroundings of massive protostars constitute an accretion disc which has numerically been shown to be subject to fragmentation and responsible for luminous accretion-driven outbursts. Moreover, it is suspected to produce close binary…
Understanding the formation of wide binary systems of very low mass stars (M $\le$ 0.1 Msun) is challenging. The most obvious route is via widely separated low-mass collapsing fragments produced through turbulent fragmentation of a…
Over a broad range of initial inclinations and eccentricities an appreciable fraction of hierarchical triple star systems with similar masses are essentially unaffected by the Kozai-Lidov mechanism (KM) until the primary in the central…