Related papers: NGC 663 as a laboratory for massive star evolution
The study of open-cluster chemical abundances provides insights on stellar nucleosynthesis processes and on Galactic chemo-dynamical evolution. In this paper we present an extended abundance analysis of 10 species (Fe, Ni, Cr, V, Sc, Si,…
We investigate two neighboring clusters in the Cygnus complex, Berkeley 86 and Berkeley 87, with a primary emphasis on the evaluation of extinction in the field of view towards and across the clusters. We also analyze their kinematic…
In this study, we utilize photometric and kinematic data from \textit{Gaia} DR3 and the {\sc ASteCA} package to analyze the sparsely studied open clusters, King 2 and King 5. For King 2, we identify 340 probable members with membership…
The presence of pre-main-sequence and low-mass stars, combined with the new data from Gaia DR3 and with 2MASS, significantly enhances the relevance of studying this cluster. We aim to accurately identify cluster members, determine…
Fundamental parameters characterizing the end-state of intermediate-mass stars may be constrained by discovering planetary nebulae (PNe) in open clusters (OCs). Cluster membership may be exploited to establish the distance, luminosity, age,…
The ultraviolet resonance wind stellar lines, the nebular optical emission lines and the higher order terms of the Balmer series and HeI absorption lines detected in the spectra of NGC 604 are interpreted using evolutionary models optimized…
(Abridged) New boron abundances for seven main-sequence B-type stars are determined from HST STIS spectroscopy around the BIII 2066A line. Boron abundances provide a unique and critical test of stellar evolution models that include…
Omega Centauri is a peculiar Globular Cluster formed by a complex stellar population. To shed light on this, we studied 172 stars belonging to the 5 SGBs that we can identify in our photometry, in order to measure their [Fe/H] content as…
Multiplicity among massive stars represents a major uncertainty in stellar evolution theory, because the extra physical processes that it introduces significantly impacts each star's structure. While multiplicity of O-type stars is fairly…
We analyse a sample of 507 evolved stars in the inner galactic Plane. We derive average ages for subsets of this sample and use those sets as beacons for the evolution of the Galaxy. In the Bulge the oldest OH/IR stars in the plane are 7.5…
We present an analysis of late-time Hubble Space Telescope Wide Field Camera 3 and Wide Field Planetary Camera 2 observations of the site of the Type Ic SN 2007gr in NGC 1058. The SN is barely recovered in the late-time WFPC2 observations,…
We present UBV photometry of the highly reddened and poorly studied open cluster Berkeley 55, revealing an important population of B-type stars and several evolved stars of high luminosity. Intermediate resolution far-red spectra of several…
Planetary Nebulae (PNe) in the Large Magellanic Cloud (LMC) offer the unique opportunity to study both the Population and evolution of low- and intermediate-mass stars, by means of the morphological type of the nebula. Using observations…
We have compiled a significantly updated and comprehensive census of massive stars in the nearby Cygnus OB2 association by gathering and homogenising data from across the literature. The census contains 169 primary OB stars, including 52…
We investigate the massive star content of NGC 3603, the closest known giant H II region. We have obtained spectra of 26 stars in the central cluster using the Baade 6.5-m telescope (Magellan I). Of these 26 stars, 16 had no previous…
We present 23 candidate X-ray binaries with luminosities down to 1.8x10^36 erg/s, in the nearby starburst galaxy NGC 4449, from observations totaling 105 ksec taken with the ACIS-S instrument on the Chandra Space Telescope. We determine…
We report the detection of a young stellar population ($\leq$100 Myrs) in the ba ckground of 9 young open clusters belonging to a homogenoeous sample of 30 star clusters in the Third Galactic Quadrant (at $217^o \leq l \leq 260^o$). Deep…
We present new astrophysical parameters for the open cluster NGC~6793 based on new CCD $UBV(RI)_{KC}$ photometry. We derived a reddening of $E(B-V) = 0.24 \pm 0.02$~mag and a heavy element abundance of $Z = 0.024$ ($[Fe/H] = +0.20$~dex).…
Due to their extreme helium abundance, the multiple stellar populations of the globular cluster NGC 2808 have been widely investigated from a photometric, spectroscopic, and kinematic perspective. The most striking feature of the…
We have analysed near-infrared NTT/SofI observations of the starburst cluster Westerlund 1, which is among the most massive young clusters in the Milky Way. A comparison of colour-magnitude diagrams with theoretical main-sequence and…