Related papers: Binary stars in the Galactic thick disc
The formation of the extended thin disc is the most spectacular event of our Galaxy in the past $\sim8$\,Gyr. To unveil this process, obtaining precise and accurate stellar ages for a large sample of stars is essential although challenging.…
Energetic outflows from main sequence stars accreting mass at very high rates might account for the powering of some eruptive objects, such as merging main sequence stars, major eruptions of luminous blue variables, e.g., the Great Eruption…
We investigate how a protoplanetary disc's susceptibility to gravitational instabilities and fragmentation depends on the mass of its host star. We use 1D disc models in conjunction with 3D SPH simulations to determine the critical…
While there are a number of proposed formation channels for subsolar mass compact objects, including black holes formed primordially, or neutron stars that form in collapsar disks, there have yet to be any conclusive observations of such…
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…
The study of the Milky Way stellar discs in the context of galaxy formation is discussed. In particular we explore the properties of the Milky Way disc using a new sample of about 550 dwarf stars for which we have recently obtained…
Evidence from the analysis of eclipsing binary systems revealed that late-type stars are larger and cooler than predicted by models, and that this is probably caused by stellar magnetic activity. In this work, we revisit this problem taking…
We study the evolution of bound pairs of star clusters by means of direct N-body simulations. Our simulations include mass loss by stellar evolution. The initial conditions are selected to mimic the observed binary star cluster NGC 2136 and…
We have recently presented observational evidence which suggests that the origin of the second generation (G2) stars in globular clusters (GCs) is due to the binary-mediated collision of primordial (G1) low-mass main-sequence (MS) stars.…
The majority of massive stars are found in close binaries which: (i) are prone to merge and (ii) are accompanied by another distant tertiary star (triples). Here, we study the evolution of the stellar post-merger binaries composed of the…
This chapter reviews the dynamical processes in young stellar clusters. The accretion of gas by individual stars affects the dynamics of the cluster, and the masses of the stars. Dynamical mass segregation cannot explain the degree of mass…
We have pursued two different methods to analyze the old stellar population near the Galactic plane, using data from the 2MASS survey. The first method is based on the isolation of the red clump giant population in the color-magnitude…
We determine relative stellar ages and metallicities mainly for about 80 elliptical galaxies in low and high density environments via the latest binary stellar population (BSP) synthesis model and test a latest hierarchical formation model…
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.…
The total mass of a distant star cluster is often derived from the virial theorem, using line-of-sight velocity dispersion measurements and half-light radii, under the implicit assumption that all stars are single (although it is known that…
The stability criteria of rapid mass transfer and common-envelope evolution are fundamental in binary star evolution. They determine the mass, mass ratio, and orbital distribution of many important systems, such as X-ray binaries, type Ia…
Context: Field stars are not always single stars, but can often be found in bound double systems. Since binary frequencies in the birth places of stars, young embedded clusters, are sometimes even higher than on average the question arises…
We present a suite of binary evolution models with massive primaries (10 $\leq$ M$_1$ $\leq$ 40 M$_\odot$) and periods and mass ratios chosen such that the systems undergo non-conservative mass transfer while the primaries have helium…
Most of massive stars form in binary or higher-order systems in clumpy, sub-structured clusters. In the very first phases of their life, these stars are expected to interact with the surrounding environment, before being released to the…
One of the suggested thick disc formation mechanisms is that they were born quickly and in situ from a turbulent clumpy disc. Subsequently, thin discs formed slowly within them from leftovers of the turbulent phase and from material…