Related papers: Two massive stars possibly ejected from NGC 3603 v…

Between 1996 and 2003 we have obtained 226 high resolution spectra of 16 stars in the field of the young open cluster NGC 6913, to the aim of constraining its main properties and study its internal kinematics. Twelve of the program stars…

Hypervelocity stars have been recently discovered in the outskirts of galaxies, such as the unbound star in the Milky Way halo, or the three anomalously fast intracluster planetary nebulae (ICPNe) in the Virgo Cluster. These may have been…

We present the discovery of the totally eclipsing long-period (P = 771.8 d) binary system WOCS 23009 in the old open cluster NGC 6819 that contains both an evolved star near central hydrogen exhaustion and a low-mass (0.45 Msun) star. This…

We present a robust methodology for identifying photometric binaries in star clusters. Using Gaia DR3, Pan-STARRS and 2MASS data, we self-consistently define the cluster parameters and binary demographics for the open clusters (OCs) NGC…

In this work we derive clues to the formation scenario and ionisation source of the lenticular galaxy NGC 3607 by means of metallicity gradients, stellar population and emission lines properties. We work with long-slit spectroscopy from…

In 2007 we reported two cometary shaped sources in the vicinity of Sgr A* (0.8" and 3.4" projected distance), named X7 and X3. The symmetry axes of the two sources are aligned to within 5 degrees in the plane of the sky and the tips of…

We present a spectroscopic analysis of the GIRAFFE and UVES data collected by the Gaia-ESO survey for the young open cluster NGC 3293. Archive spectra from the same instruments obtained in the framework of the `VLT-FLAMES survey of massive…

ABRIDGED: A detailed 2D study of the central region of NGC5253 has been performed to characterize the stellar and ionized gas structure as well as the extinction distribution, physical properties and kinematics of the ionized gas in the…

We study three processes that eject hypervelocity (>10^3 km/s) stars from the Galactic center: (i) close encounters of two single stars; (ii) tidal breakup of binary stars by the central black hole, as originally proposed by Hills; and…

A majority of massive stars are part of binary systems, a large fraction of which will inevitably interact during their lives. Binary-interaction products (BiPs), i.e. stars affected by such interaction, are expected to be commonly present…

VLA neutral hydrogen observations of the shell elliptical NGC 3656 reveal an edge-on, warped minor axis gaseous disk (M_HI ~ 2.10^9 Msun) extending 7 kpc. HI is also found outside the optical image, on two complexes to the North-East and…

A deep (~70%) and extended (~150 days) eclipse was seen towards the young multiple stellar system V773 Tau in 2010. We interpret it as due to the passage of a circumbinary disk around the B components moving in front of the A components.…

The Sun was born in a clustered environment with 10,000 other stars. Being an isolated star today, the Sun must have left the nest. We do not directly know when that happened, how violent the ejection was, or how far the Solar siblings have…

We study the dynamical interaction in which the two single runaway stars AE Aurigae and mu Columbae and the binary iota Orionis acquired their unusually high space velocity. The two single runaways move in almost opposite directions with a…

New ALMA CO, HCO+, and 100 GHz continuum observations and Gemini NIFS K-band spectra are combined with previous radio to X-ray data to study Feature i, a highly luminous starburst clump on an outer arm of the interacting galaxy NGC 2207.…

Using the NANTEN2 Observatory, we carried out a molecular line study of high-mass star forming regions with reflection nebulae, NGC 2068 and NGC 2071, in Orion in the 13CO(J=2-1) transition. The 13CO distribution shows that there are two…

X-ray and near-IR surveys of the central 2x0.8 degrees of the Galactic Centre have revealed a population of X-ray bright massive stars. However, the nature of the emission, originating in a wind collision zone or via accretion onto a…

We present spectroscopic observations of the central star clusters in NGC 5253 the aim of which is to search for WC stars. Our observations show the presence of Wolf-Rayet (WR) stars not only of WN but also of WC subtype in two star forming…

We use mid-IR images from the Spitzer Cygnus~X Legacy Survey to search for stellar bowshocks, a signature of early type "runaway" stars with high space velocities. We identify ten arc-shaped nebulae containing centrally located stars as…

Analyzing the dynamical state of nearby young massive star clusters is essential understanding star cluster formation and evolution during their earliest stages. In this work we analyze the stellar and gas kinematics of the young massive…