Context. The total mass of a cluster, which is the main parameter determining its ability to host more than one stellar generation, may constitute a threshold below which the cluster is able to form only a single stellar population. Aims: Our goal is to investigate the existence of star-to-star variations in CN and CH band strengths, which are

Classical barium stars are binary systems which consist of a late-type giant enriched in carbon and slow neutron capture (s-process) elements and an evolved white dwarf (WD) that is invisible at optical wavelengths. The youngest observed barium stars are surrounded by planetary nebulae (PNe), ejected soon after the wind accretion of polluted

The most extreme ultraluminous X-ray sources (ULXs), with LX > 5 × 1040 erg s-1, are amongst the best candidates for hosting intermediate-mass black holes (IMBHs) in the haloes of galaxies. Jet radio emission is expected from a sub-Eddington accreting IMBH in the low/hard (radio bright) state. In a search for such IMBH jet radio emission, we have

A prevalent but untested paradigm is often used to describe the prominence-cavity system: the cavity is under-dense because it is evacuated by supplying mass to the condensed prominence. The thermal non-equilibrium (TNE) model of prominence formation offers a theoretical framework to predict the thermodynamic evolution of the prominence and the

Aims: We explore the relations between physical and orbital properties of planets and properties of their host stars to identify the main observable signatures of the formation and evolution processes of planetary systems. Methods: We used a large sample of FGK dwarf planet-hosting stars with stellar parameters derived in a homogeneous way from the

Fullerene C60 and C70 were discovered in 2010 by means of infrared spectroscopy in a series of astrophysical objects like for example planetary and protoplanetary nebulae and reflection nebulae. These discoveries suggest that C60 and C70 must be widespread in the interstellar medium and may contribute as neutral species or as radical cation (C60+•