Related papers: Fitting the young main-sequence; distances, ages a…

We present revised stellar ages for 23 pre-main sequence K- and M-type stars in the Upper Scorpius star-forming region, derived by using stellar dynamical masses to constrain isochronal ages from five pre-main sequence stellar evolutionary…

We have used Washington photometry for 90 star cluster candidates of small angular size -typically ~ 11" in radius- distributed within nine selected regions in the inner disc of the Large Magellanic Cloud (LMC) to disentangle whether they…

Rotation periods and projected equatorial velocities of pre-main-sequence (PMS) stars in star forming regions can be combined to give projected stellar radii. Assuming random axial orientation, a Monte-Carlo model is used to illustrate that…

Stars in open clusters are powerful probes of the intervening Galactic magnetic field, via background starlight polarimetry, because they provide constraints on the magnetic field distances. We use 2MASS photometric data for a sample of 31…

The outcome of the formation of massive stars is an important anchor point in their evolution. It provides insight into the physics of the assembly process, and sets the conditions for stellar evolution. We characterize a population of 18…

We present a new method for the evaluation of the age and age-spread among pre-main-sequence (PMS) stars in star-forming regions in the Magellanic Clouds, accounting simultaneously for photometric errors, unresolved binarity, differential…

A high number of embedded clusters is found in the Galaxy. Depending on the formation scenario, most of them can evolve to unbounded groups that are dissolved within a few tens of Myr. A systematic study of young stellar clusters showing…

The detached eclipsing binary V20 in the old, metal--rich open cluster NGC 6791 is studied in order to determine highly accurate masses and radii of its components. This allows the cluster age to be established with high precision, using…

We fit the colour-magnitude diagrams of stars between the zero-age main-sequence and terminal-age main sequence in young clusters and associations. The ages we derive are a factor 1.5 to 2 longer than the commonly used ages for these…

Using high-precision observations from the space-based \textit{Gaia} and \textit{TESS} missions, complemented by ground-based spectroscopic data and multi-band photometric surveys, we perform a detailed investigation of the Galactic open…

We present a new method to derive the age of young (<0.7 Gyr) L dwarfs based on their near-infrared photometry, colours, and distances. The method is based on samples of L dwarfs belonging to the Upper Sco association (5 Myr), the Alpha Per…

We present WFPC2 and ground-based VI photometry of NGC 121 and a nearby field in the outer SMC. For NGC 121, we measure a true distance modulus of (m-M)0 = 18.96 +/- 0.04 (distance of 61.9 +/- 1.1 kpc), age of 10.6 +/- 0.5 Gyr, metallicity…

Using tracer particles embedded in self-gravitating shearing sheet N-body simulations, we investigate the distance in guiding centre radius that stars or star clusters can migrate in a few orbital periods. The standard deviations of guiding…

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 very young clusters, stellar age distribution is the empirical proof of the duration of star formation (SF) and of the physical mechanisms involved in the process. We derived accurate stellar ages for the cluster NGC6530, associated with…

We combine archival images for the nearby galaxy M33 (Triangulum Galaxy) from the ultraviolet (UV) to the infrared (IR) to derive ages, masses, and extinctions for the young star cluster population, and compare our physical parameters with…

We present $UBVI_C$ CCD photometry of the young open cluster Be 59 with the aim to study the star formation scenario in the cluster. The radial extent of the cluster is found to be $\sim$ 10 arcmin (2.9 pc). The interstellar extinction in…

Four young star clusters were studied in order to characterize their anomalous extinction or variable reddening that could be due to a possible contamination by dense clouds or circumstellar effects. The extinction law (Rv) was evaluated by…

We use the first data release of the Gaia mission to explore the three dimensional arrangement and the age ordering of the many stellar groups towards the Orion OB association, aiming at a new classification and characterization of the…

The distance to the Orion Nebula Cluster (ONC) is estimated using the rotational properties of its low-mass pre main-sequence (PMS) stars. Rotation periods, projected equatorial velocities and distance-dependent radius estimates are used to…