相关论文: Binary mass ratios: system mass not primary mass
Two main features of the observable distribution of visible matter are the space correlations of galaxy positions and the mass function of galaxies. As discussed in Pietronero and Sylos Labini on this issue ([1], see also [2],[3]), the…
Brown dwarfs are intermediate objects between planets and stars. The lower end of the brown-dwarf mass range overlaps with the one of massive planets and therefore the distinction between planets and brown-dwarf companions may require to…
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…
To determine the parameters (masses, orbital period) of a binary, one requires among others the inclination, which is best determined from a visual orbit. The next generation of interferometers can provide visual orbits for a large number…
We infer the dynamical masses of stars across the Hertzsprung-Russell (H-R) diagram using wide binaries from the Gaia survey. Gaia's high-precision astrometry measures the wide binaries' orbital motion, which contains the mass information.…
Binary stars can interact via mass transfer when one member (the primary) ascends onto a giant branch. The amount of gas ejected by the binary and the amount of gas accreted by the secondary over the lifetime of the primary influence the…
In this paper, some statistical distributions of wide pairs included in Double Star Catalogue are investigated. Frequency distributions and testing hypothesis are derived for some basic parameters of visual binaries. The results reached…
Binary/multiple status can affect stars at all stages of their lifetimes: evolution onto the main sequence, properties on the main sequence, and subsequent evolution. 5 $M_\odot$ stars have provided a wealth of information about the binary…
We have undertaken a series of hydrodynamic + N-body simulations in order to explore the properties of young stars. Our results suggest that the IMF may be sensitive to environment in its substellar region, with more brown dwarfs being…
Observations of binaries have traditionally provided the means for ascertaining stellar masses. Here, we use the published data on 8 pre-main-sequence pairs to gauge the accuracy of our own, recently calculated, evolutionary tracks (Palla &…
Binary stars and their interactions shape the formation of compact binaries, supernovae, and gravitational wave sources. The efficiency of mass transfer - the fraction of mass retained by the accretor during binary interaction - is a…
Sun-like stars are known to host a paucity of brown dwarf companions at close separations. Direct imaging surveys of intermediate-mass stars have suggested that the brown dwarf desert may be fundamentally a feature in the mass ratio.…
Stellar multiplicity is an ubiquitous outcome of the star formation process. Characterizing the frequency and main characteristics of multiple systems and their dependencies on primary mass and environment is therefore a powerful tool to…
In this paper I show that the concept of relativistic beaming -- the process by which light emitted by a fast moving sources is lensed towards the direction of motion -- can be easily extended to model the signal from both the star and any…
We compile observations of early-type binaries identified via spectroscopy, eclipses, long-baseline interferometry, adaptive optics, common proper motion, etc. Each observational technique is sensitive to companions across a narrow…
It is argued that apart from the well known dependence of the Am phenomenon on the mass, age (effective temperature, gravity) and rotation there is also a complex dependence on the orbital parameters in binary systems. This is why the…
In this work we present a study of binary systems in a metal-poor sample of solar type stars. The stars analyzed were rejected from two planet search samples because they were found to be binaries. Using available radial velocity and…
Binary galaxies are modeled as point-masses obeying the non-Newtonian MOND and Mannheim-Kazanas (MKG) theories of gravity. Random samples of such systems are generated by means of Monte Carlo simulations of binary orbits. Model pairs have…
A long standing and unverified prediction of binary star evolution theory is the existence of a population of white dwarfs accreting from sub-stellar donor stars. Such systems ought to be common, but the difficulty of finding them, combined…
Although many models have been proposed, the physical mechanisms responsible for the formation of low-mass brown dwarfs are poorly understood. The multiplicity properties and minimum mass of the brown-dwarf mass function provide critical…