Related papers: Binary stars in the Galactic thick disc

In the Milky Way disk there is a strong trend linking stellar age to surface element abundances. Here we explore this relationship with a dataset of 8,803 red-giant and red-clump stars with both asteroseismic data from NASA Kepler Mission…

Stellar activity is fundamental to stellar evolution and the formation and habitability of exoplanets. The interaction between convective motions and rotation in cool stars results in a dynamo process that drives magnetic surface activity.…

We present numerical simulations modeling the orbital evolution of very wide binaries, pairs of stars separated by over ~1000 AU. Due to perturbations from other passing stars and the Milky Way's tide, the orbits of very wide binary stars…

[Abridged] Ensemble studies of red-giant stars with exquisite asteroseismic, spectroscopic, and astrometric constraints offer a novel opportunity to recast and address long-standing questions concerning the evolution of stars and of the…

We postulate that most stars are born in aggregates of binary systems which are dynamically equivalent to the `dominant mode cluster'. The initial binary orbits are consitent with pre-main sequence data. Stellar masses are paired at random…

We explore the effects of dynamical evolution in dense clusters on the companion mass ratio distribution (CMRD) of binary stars. Binary systems are destroyed by interactions with other stars in the cluster, lowering the total binary…

Recent observations of binary stars in the Galactic field show that the binary fraction and the mean orbital separation both decrease as a function of decreasing primary mass. We present $N$-body simulations of the effects of dynamical…

The massive (13,000-26,000 Msolar), young (15-30 Myr) Large Magellanic Cloud star cluster NGC 1818 reveals an unexpected increasing binary frequency with radius for F-type stars (1.3-2.2 Msolar). This is in contrast to many older star…

Binary stars produce an array of dramatic astrophysical phenomena. They allow us to probe stellar structure, nuclear physics, and gravitational wave physics. They also produce the powerful supernovae that allow us to measure the scale of…

The Milky Way is a unique laboratory, where stellar properties can be measured and analyzed in detail. In particular, stars in the older populations encode information on the mechanisms that led to the formation of our Galaxy. In this…

Globular clusters contain many stars with surface abundance patterns indicating contributions from hydrogen burning products, as seen in the anti-correlated elemental abundances of e.g. sodium and oxygen, and magnesium and aluminium.…

The high multiplicity of massive stars in dense, young clusters is established early in their evolution. The mechanism behind this remains unresolved. Recent results suggest that massive protostars may capture companions through disk…

The majority of stars in known star-forming regions are located in binary systems. Although the separation distribution of these populations varies from one region to another, most peak between a few and several tens of AU. Given the >100…

A magnetic dynamo driven by differential rotation generated when stars merge can explain strong fields in certain classes of magnetic stars, including the high field magnetic white dwarfs (HFMWDs). In their case the site of the differential…

Studies of young clusters have shown that a large fraction of O-/early B-type stars are in binary systems, where the binary fraction increases with mass. These massive stars are present in clusters of a few Myrs, but gradually disappear for…

Young binaries within dense molecular clouds are subject to dynamical friction from ambient gas. Consequently, their orbits decay, with both the separation and period decreasing in time. A simple analytic expression is derived for this…

We apply probabilistic generative modelling of colour-magnitude diagrams to six young Galactic open star clusters and determine their mass functions, binary mass-ratio distributions, and the frequencies of binary stars. We find that younger…

Be stars are rapidly rotating B type stars. The origin of their rapid rotation is not certain, but binary interaction remains to be a possibility. In this work we investigate the formation of Be stars resulting from mass transfer in…

A significant number of intermediate age clusters (1-2 Gyr) in the Magellanic Clouds appear to have multiple stellar populations within them, derived from bi-modal or extended main sequence turn offs. If this is interpreted as an age…

In our current interpretation of the hierarchical structure of the universe it is well established that galaxies collide and merge with each other during their lifetime. If massive black holes (MBHs) reside in galactic centres, we expect…