Related papers: A rotational age for the open cluster NGC 2281

Earlier measurements of the masses and radii of the detached eclipsing binary V20 in the open cluster NGC 6791 were accurate enough to demonstrate that there are significant differences between current stellar models. Here we improve on…

We present deep photometric observations of the open cluster NGC 2477 using HST/WFPC2. By identifying seven cluster white dwarf candidates, we present an analysis of the white dwarf age of this cluster, using both the traditional method of…

An important aspect in the evolutionary scenario of cool stars is their rotation and the rotationally induced magnetic activity and interior mixing. Stars in open clusters are particularly useful tracers for these aspects because of their…

We continue our study of rich Galactic clusters by presenting deep CCD observations of both NGC 2168 (M35) and NGC 2323 (M50). Both clusters are found to be rich (NGC 2168 contains at least 1000 stars brighter than V = 22 and NGC 2323…

We present the $UBVRI$ CCD photometry in the region of the open cluster NGC 2421. Radius of the cluster is determined as $\sim$ 3$^\prime$.0 using stellar density profile. Our Study indicates that metallicity of the cluster is $Z \sim$…

The rotational evolution of cool dwarfs is poorly constrained after around 1-2 Gyr due to a lack of precise ages and rotation periods for old main-sequence stars. In this work we use velocity dispersion as an age proxy to reveal the…

Deep CCD photometry down to V=24.5 is presented for the old Magellanic Globular cluster NGC 2257. The main result cna be summarized as follows: i) the RGB Bump has been detected at V=18.7+-0.1, and is compatible with determination of this…

We use the Wide Field Camera 3 onboard the Hubble Space Telescope to obtain deep, high-resolution photometry of the young (age ~ 300 Myr) star cluster NGC1856 in the Large Magellanic Cloud. We compare the observed colour-magnitude diagram…

Open clusters are ideal targets for searching for transiting Hot Jupiters. They provide a relatively large concentration of stars on the sky and cluster members have similar metallicities, ages and distances. Fainter cluster members are…

We present the results of a 5 month photometric time-series survey for stellar rotation over a 40'x40' field on the 150 Myr open cluster M35. We report rotation periods for 441 stars and determine their cluster membership and binarity based…

We present spectroscopic ages, metallicities, and [alpha/Fe] ratios for 70 globular clusters in M31 that were derived from Lick line-index measurements. In addition to a population of old (>10 Gyr) globular clusters with a wide range of…

The zero-age main sequence (ZAMS) is a critical phase for stellar angular momentum evolution, as stars transition from contraction-dominated spin-up to magnetic wind-dominated spin-down. We present the first robust observational constraints…

Young star clusters enable us to study the effects of stellar rotation on an ensemble of stars of the same age and across a wide range in stellar mass and are therefore ideal targets for understanding the consequences of rotation on stellar…

NGC 2355 is an old open cluster in the outer part of the galactic disk (l=203 deg, b=+11 deg) which has been little studied until now. This paper presents the first astrometric and spectroscopic investigation of this cluster. We have…

We report on CCD optical (B and V passbands) and near IR (J and K bands) observations in the region of the old open cluster NGC 2141. By combining the two sets of photometry (500 stars in common) we derive new estimates of the cluster…

High-dispersion spectra of 89 potential members of the old, super-metal-rich open cluster, NGC 6253, have been obtained with the HYDRA multi-object spectrograph. Based upon radial-velocity measurements alone, 47 stars at the turnoff of the…

We develop the white dwarf luminosity function (LF) of the old open cluster NGC 188 in order to determine a lower limit to the age of the cluster by using the faint end of the cooling sequence. To produce an extensive sequence of the…

We report the serendipitous young Large Magellanic Cloud cluster, NGC 1971, exhibits an extended main-sequence turnoff (eMSTO) possibly originated by mostly a real age spread. We used CT1 Washington photometry to produce a colour-magnitude…

The first CCD UBV(RI) photometric study in the area of the doubtful open cluster NGC 2129 is presented. Photometry of a field offset 15 arcmin northward is also provided, to probe the Galactic disk population toward the cluster. Using star…

We present a kinematic and dynamical analysis of six Galactic open clusters NGC~2204, NGC~2660, NGC~2262, Czernik~32, Pismis~18, and NGC~2437, using \textit{Gaia}~DR3. We used Bayesian and Gaussian Mixture Model (GMM) methods to identify…