Tabular mass solutions for close binaries

The solutions for the mass of single-line close binaries with Main-Sequence primaries are given in a tabular form as a result of the application of the mass-luminosity relation. Linear interpolation in a compact bi-variate table suffices to give the values of mass of the two components for a wide range of masses and to a very good approximation. The indeterminacy of the solutions depending on the formulation of the mass-luminosity relation for the primaries is discussed, as well as the condition of filling up their Roche lobes by the secondaries.     

Absolute dimensions of 140 close binary systems

The absolute dimensions of 140 close binaries have been computed. These systems have been extracted from recent catalogues of photometric and spectroscopic elements.     

Evolutionary stages of visual binary components

In the assumption of a coeval origin of the components of visual binaries, the possible evolutionary stages of the stars forming a system can be studied on the basis of the differences in apparent visual magnitudes and color indices. According to such differences, a subdivision of systems in groups depending on the evolutionary stages of the components has been investigated. Some rough limiting estimates of the masses can be attempted. A comparison with observations is given.

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Résumé Dans l'hypothèse de l'origine contemporaine pour les étoiles composantes des systèmes binaires visuels on a recherché les phases évolutives possibles en se basant sur les différences des magnitudes apparentes visuelles et des indices de la couleur. En conséquence on a subdivisé les systèmes par groupes par rapport aux phases évolutives des composantes. On a donné des évaluations approximatives limites pour les masses et une comparaison avec les observations.

     

Visual binary systems in the solar neighbourhood: The mass-ratio distribution

Nearby visual binaries, with both components on the Main Sequence, have been considered in order to obtain information about the distribution of their mass ratios. These systems have their primary components ranging from A0 to G9. The data have been corrected for selection effects and the differences V of the visual magnitudes have been transformed into mass-ratio values.The frequency distribution of the mass ratios appears to be bimodal, with a peak around unity and a maximum at about 0.25. It is suggested that this feature may be indicative of different mechanisms of formation for wide binaries.     

Geological and hydrogeological reconstruction of the main aquifers of the Maltese islands

Hydrogeology Journal - Geological and hydrogeological conceptualizations of the five main aquifers of Malta were performed by means of characterization of the groundwater bodies’ geometries...     

On the roche constants for Main-Sequence binaries

The ratiosC ₁/C ₂ of the constants defining the equipotential surfaces which describe the external forms of the components of a close binary system have been calculated on the basis of evolutionary models. Theoretical systems have been considered allowing for a wide range of input parameters (masses and separation) and taking into account the evolutionary effects on the radii of the stars during their Main-Sequence lifetime. The systems have not undergone any transfer of matter and are representative of detached binaries with Main-Sequence components. The ratios of the constants are confined in limited intervals and, for the highest values of the mass-ratio, they are clustered around the unit.     

A quest for initial parameters of the semi-detached eclipsing binary μ1Sco

By assigning to the semi-detached system ¹Sco the age of the Sco OB2 association (to which the binary belongs), it is possible to search for its initial characteristics. A model in agreement with the observational data is achieved by assuming a mass and momentum loss from the system during the phase of mass transfer between the components.     

Visual binary systems in the solar neighbourhood: A question of their separations

The separations between the components of nearby visual binaries are investigated. For Main-Sequence stars in the spectral range F0-M7 the distribution of the separations is independent from the spectral type of the primary component. A decrease of the limiting upper separation from the early to late-type systems found by Abt is probably due to selective constraints.