Related papers: A Search for variable stars in the four open star …
The analysis of the distribution of stars in open clusters may yield important information on the star formation process and early dynamical evolution of stellar clusters. Here we address this issue by systematically characterizing the…
Blue straggler stars (BSS) are well studied in globular clusters but their systematic study with secure membership determination is lacking in open clusters. We use Gaia DR2 data to determine accurate stellar membership for four…
We have obtained CCD BVI imaging of the old open clusters Berkeley 32 and King 11. Using the synthetic colour-magnitude diagram method with three different sets of stellar evolution models of various metallicities, with and without…
We present results of multi-epoch (fourteen nights during 2007-2010) $V$-band photometry of the cluster NGC 1893 region to identify photometric variable stars in the cluster. The study identified a total of 53 stars showing photometric…
We have analysed the photometric data obtained with the STEREO spacecraft for 558 non-magnetic chemically peculiar (CP) stars to search for rotational and pulsational variability. Applying the Lomb-Scargle and the phase dispersion…
Variable stars have been identified for the first time in the very metal-poor Blue Compact dwarf galaxy IZw18, using deep multi-band (F606W, F814W)time-series photometry obtained with the Advanced Camera for Surveys (ACS) on board the…
We report here CCD $I$-band time-series photometry of a young (2$-$5 Myr) cluster NGC 2282 to identify and understand the variability of pre-main-sequence (PMS) stars. The $I$-band photometry, down to $\sim$ 20.5 mag, enables us to probe…
We present UBVRcIc photometric study of three intermediate age open star clusters NGC 381, NGC 2360, and Berkeley 68 (Be 68). We examine the cluster membership of stars using recently released Gaia DR2 proper motions and obtain a total of…
We used four-year baseline HST/WFC3 IR observations of the Galactic Centre in the F153M band (1.53 micron) to identify variable stars in the central ~2.3'x2.3' field. We classified 3845 long-term (periods from months to years) and 76…
We searched for Delta Scuti-type pulsations amongst known and candidate Gamma Doradus stars. We acquired 270 h of observations and monitored a total of 26 stars. One target, HD 209295, turned out to be a member of both classes of pulsating…
We present the results of a long-term variability survey of the old open cluster NGC 6791. The BVI observations, collected over a time span of 6 years, were analyzed using the ISIS image subtraction package. The main target of our…
A rarely studied open cluster, King 1 is observed using the 1.3m telescope equipped with 2k x 4k CCD at the Vainu Bappu Observatory, India. We analyse the photometric data obtained from the CCD observations in both B and V bands. Out of 132…
Using the Southeastern Association for Research in Astronomy 0.6 meter telescope located at Cerro Tololo, we searched for variable stars in the southern globular cluster NGC 6584. We obtained images during 8 nights between 28 May and 6 July…
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…
The sixth part of the OGLE-III catalog of Variable Stars presents \delta Sct pulsators in the Large Magellanic Cloud. Altogether 2786 variable stars were found and amongst them 92 are multi-mode objects, including 67 stars pulsating in the…
We have performed multiband UBVRcIcJHKs photometry of two young clusters located at large Galactocentric distances in the direction of the Perseus spiral arm. The obtained distances and colour excesses amount to 3.9+-0.11 kpc,…
The open cluster Berkeley 90 is the home to one of the most massive binary systems in the Galaxy, LS III +46$^{\circ}$11, formed by two identical, very massive stars (O3.5 If* + O3.5 If*), and a second early-O system (LS III +46$^{\circ}$12…
A detailed analysis of ground-based CCD UBV photometry and space-based Gaia Data Release 3 (DR3) data for the open clusters King 6 and NGC 1605 was performed. Using the pyUPMASK algorithm on Gaia astrometric data to estimate cluster…
Using the United Kingdom Infrared Telescope on Mauna Kea, we have carried out a new near-infrared J, H, K monitoring survey of almost a square degree of the star-forming Orion Nebula Cluster with observations on 120 nights over three…
We present VI-band photometry for stars in the metal-rich globular cluster NGC 6496. Our time-series data were cadenced to search for long period variables (LPVs) over a span of nearly two years, and our variability search yielded the…