Related papers: Detection of new variable stars in the SMC cluster…
We obtained a series of more than two hundred R-band CCD images for the crowded central (115"x77") region of the metal-poor globular cluster M15 with an angular resolution of 0.5"-0.9" in most images. Optimal image subtraction was used to…
We present B, V and I CCD light curves for 101 variable stars belonging to the globular cluster NGC2419, 60 of which are new discoveries, based on datasets obtained at the TNG, SUBARU and HST telescopes. The sample includes 75 RR Lyrae…
As first Paper of a series devoted to study the old stellar population in clusters and fields in the Small Magellanic Cloud, we present deep observations of NGC121 in the F555W and F814W filters, obtained with the Advanced Camera for…
We have used DOLORES at the TNG to obtain B,V time series photometry of NGC 2419, one of the most distant and bright clusters in the Galactic halo. These data will be used to study its variable star population in order to check whether the…
We present a new search for variable stars in the Galactic globular cluster M28 (NGC 6626). The search is based on a series of BVI images obtained with the SMARTS Consortium's 1.3m telescope at Cerro Tololo Inter-American Observatory,…
This is the second in a series of papers studying the variable stars in Large Magellanic Cloud globular clusters. The primary goal of this series is to study how RR Lyrae stars in Oosterhoff-intermediate systems compare to their…
We have carried out a new photometric study of the remote Galactic globular cluster NGC 2419, using proprietary and archive B,V,I time-series CCD photometry of the cluster, that allowed us to discover a large number of new variable stars…
We present the preliminary results of an image-subtraction analysis of the Galactic globular cluster M79 (NGC 1904), as well as a new investigation of the variable star population in NGC 1851. Both M79 and NGC 1851 have been previously…
We present time-series B, V photometry of NGC 6229, obtained with the purpose of providing the first extensive CCD variability study of this cluster. As a result, we were able to obtain periods for all NGC 6229 variables, with the exception…
Five fields located close to the center of the globular cluster NGC 104=47 Tuc were surveyed in a search for variable stars. We present V-band light curves for 42 variables. This sample includes 13 RR Lyr stars -- 12 of them belong to the…
The central part of the globular cluster NGC 288 was surveyed in a search for short-period variable stars. We obtained the V-band light curves for 4 SX Phe stars and 2 RR Lyrae variables, five of which are new discoveries. All SX Phe stars…
We present results from ACS and WFPC observations in the low luminosity galaxy NGC 45. We identified 28 young star cluster candidates. While the exact values of age, mass, and extinction depend somewhat on the choice of SSP models, we find…
The field of the globular cluster M10 (NGC 6254) was monitored between 1998 and 2015 in a search for variable stars. V -light curves were derived for 40 variables or likely variables, most of which are new detections. Proper motions…
We present the analysis of 26 nights of V and I time-series observations from 2011 and 2012 of the globular cluster M 30 (NGC 7099). We used our data to search for variable stars in this cluster and refine the periods of known variables; we…
The image subtraction technique applied to study variable stars in globular clusters represented a leap in the number of new detections, with the drawback that many of these new light curves could not be transformed to magnitudes due to the…
The variable star population of the galactic globular cluster NGC 1851 (C0512-400) has been studied by CCD photometry, from observations made in the B, V, and I bands during 1993-4. Light curves are presented for 29 variables, seven of…
(Abridged) We present CCD BVI photometry of 85 variable stars from the field of the globular cluster NGC 6934. The photometry was obtained with the image subtraction package ISIS. 35 variables are new identifications: 24 RRab stars, 5 RRc…
We present results of a UBVIc variability survey in the young open cluster NGC 2244. In total, we found 245 variable stars. Most of them, 211 stars, are variables with irregular variations. Furthermore, 23 periodic variables were found. We…
We present time-series $BVI$ photometry for the Galactic globular cluster NGC 6402 (M14). The data consists of $\sim$137 images per filter, obtained using the 0.9m and 1.0m SMARTS telescopes at the Cerro Tololo Inter-American Observatory.…
We used a combination of optical and near-UV Hubble Space Telescope photometry and FLAMES/ESO-VLT high-resolution spectroscopy to characterize the stellar content of the old and massive globular cluster (GC) NGC121 in the Small Magellanic…