Related papers: Physical parameters of pre-main sequence stars in …

Pre-main sequence (PMS) models provide invaluable tools for the study of star forming regions as they allow to assign masses and ages to young stars. Thus it is of primary importance to test the models against observations of PMS stars with…

We discuss the nature of eleven Possible Open Cluster Remnants (POCRs) by using absolute proper motions from the Southern Proper Motion (SPM) Program 3 (Girard et al. 2004) combined with near infrared photometry from 2MASS. The analysis is…

We present UBVRI photometry of stars in the field of the intermediate-age open cluster NGC 559. By determining the stellar membership probabilities derived through a photometric and kinematic study of the cluster, we identify the 22 most…

In this study, the structural and basic astrophysical parameters of the poorly studied open cluster Berkeley 6 are calculated. Analyses of the cluster are carried out using the third photometric, spectroscopic, and astrometric data release…

Photographic photometries of 789 stars in the region of the open clusters NGC1750 and NGC1758 are derived from a set of 8 photometric plates. According to the astronomical data including proper motions, positions and membership…

Star clusters are superb astrophysical laboratories containing cospatial and coeval samples of stars with similar chemical composition. We have initiated the Sejong Open cluster Survey (SOS) - a project dedicated to providing homogeneous…

In case of pre-main sequence objects, the only way to determine age and mass is by fitting theoretical isochrones on color-magnitude (alternatively luminosity-temperature) diagrams. Since young stellar objects exhibit photometric…

Star clusters are good tracers for formation and evolution of galaxies. We compared different fitting methods by using spectra (or by combining photometry) to determine the physical parameters. We choose a sample of 17 star clusters in M33,…

We report the discovery of low-mass PMS stars in the younger subgroup of the Cepheus OB3 association, Cep OB3b, using {\it UBVI} CCD photometry and spectroscopy. The location of a PMS is well defined in a V versus (V-I) colour-magnitude…

We have undertaken a systematic study of pre-main sequence (PMS) stars spanning a wide range of masses (0.5 - 4 Msolar), metallicities (0.1 - 1 Zsolar) and ages (0.5 - 30 Myr). We have used the Hubble Space Telescope (HST) to identify and…

This study outlines a detailed investigation using CCD {\it UBV} and {\it Gaia} DR3 data sets of the two open clusters Ruprecht 1 (Rup-1) and Ruprecht 171 (Rup-171). Fundamental astrophysical parameters such as color excesses, photometric…

Sensitive imaging X-ray observations of young stellar clusters (YSCs, ages less than about 10 Myr) are valuable tools for the acquisition of an unbiased census of cluster members needed for Initial Mass Function (IMF) studies. Several dozen…

This work presents the first large-scale photometric variability survey of the intermediate age (~200 Myr) open cluster M11. Thirteen nights of data over two observing seasons were analyzed (using crowded field and ensemble photometry…

This paper reports results from our long-term $BV(RI)_{c}$ photometric CCD observations of eight pre-main-sequence stars collected from June 2008 to October 2022. These stars are located in the young open cluster Trumpler 37, in the field…

One of the very first steps astronomers working in stellar physics perform to advance in their studies, is to determine the most common/relevant physical parameters of the objects of study (effective temperature, bolometric luminosity,…

We investigate the nature of 4 young and low-mass open clusters (OCs) located in the $2^{nd}$ and $3^{rd}$ quadrants with near-IR 2MASS photometry (errors $<0.1$ mag). After field decontamination, the colour-magnitude diagrams (CMDs)…

We present a new technique to fit color-magnitude diagrams of open clusters based on the Cross-Entropy global optimization algorithm. The method uses theoretical isochrones available in the literature and maximizes a weighted likelihood…

Using \textit{Hubble Space Telescope} images from the PHAT and PHAST surveys, we construct an updated catalogue of 747 OB cluster (OBC) candidates. We introduce a dimensionless structural metric, the trace coefficient of variation ($CV_{\rm…

We present a VI photometric catalogue towards the open cluster Cr 121. XMM-Newton and ROSAT data are used to discover a low-mass pre-main sequence (PMS) along this sight-line. de Zeeuw et al (1999) identified Cr 121 as a moving group, using…

Stochasticity of bright stars introduces uncertainty and bias into derived structural parameters of star clusters. We have simulated a grid of cluster $V$-band images, observed with Subaru Suprime-Cam with age, mass, and size representing a…