Related papers: Variable Stars in Large Magellanic Cloud Globular …
We present the results of our new study of known RR Lyrae variable stars. All observations available for these stars in the Catalina Surveys were analyzed, and double-mode variations were identified. We studied the Petersen diagram and…
The VVV is currently surveying the central regions of the Milky Way at near-infrared wavelengths, including 36 known Galactic globular clusters. We already have data in several filters to generate their color-magnitude diagrams. We also…
This work is part of an effort to detect secular variable objects in large scale surveys by analysing their path in color-magnitude diagrams. To this aim, we first present the variability morphologies in the V/V-I diagram of several types…
As a result of the reanalysis of the OGLE-I observations by means of the image subtraction method, we present the first part of a catalog, consisting of the data for variable stars in four Galactic fields observed by the OGLE-I, viz. MM1-A,…
We study the Large Magellanic Cloud (LMC) star clusters R 127 and R 128 using imaging and spectroscopy obtained at the ESO NTT telescope. An advanced image restoration technique allows us to resolve these two clusters into at least 14 and…
I point out that the Oosterhoff dichotomy for globular cluster and field RR Lyrae (RRL) stars may place the strongest constraints so far on the number of dwarf spheroidal-like protogalactic fragments that may have contributed to the…
This paper presents the initial results of a multi-site photometric programme to examine the extraordinary behaviour displayed by 18 R Coronae Borealis (RCB) stars in the Magellanic Clouds (MCs). RCB stars exhibit a unique variability…
The eighth part of the OGLE-III Catalog of Variable Stars (OIII-CVS) contains type II Cepheids in the Small Magellanic Cloud (SMC). The sample consists of 43 objects, including 17 BL Her, 17 W Vir and 9 RV Tau stars (first examples ever…
We present mean horizontal branch absolute magnitudes and iron abundances for a sample of 39 globular clusters. These quantities were calculated in an unprecedented homogeneous fashion based on Fourier decomposition of ligt curves of RR…
We present an analysis of \emph{VI} CCD time-series photometry of the Oo II type globular cluster M92. The variable star population of the cluster is studied with the aim of revising their classifications, identifications, frequency spectra…
We present the first edition of a catalog of variable stars found in the Magellanic Clouds using OGLE-II data obtained during four years: 1997-2000. The catalog covers about 7 square degrees of the sky - 21 fields in the Large Magellanic…
We present an upgrade of the OGLE Collection of RR Lyrae stars in the Galactic bulge and disk. The size of our sample has been doubled and reached 78 350 RR Lyr variables, of which 56 508 are fundamental-mode pulsators (RRab stars), 21 321…
The new data for Cepheids and RR Lyrae stars of the Optical Gravitational Lensing Experiment (OGLE-III) survey allow us to study the three-dimensional distribution of stars corresponding to young (a few tens to a few hundreds of millions of…
Obtain time-series photometry of the very crowded central regions of Galactic globular clusters with better angular resolution than previously achieved with conventional CCDs on ground-based telescopes to complete, or improve, the census of…
We present new optical (BVI) time-series data for the evolved variable stars in the Carina dwarf spheroidal galaxy. The quality of the data and the observing strategy allowed us to identify 14 new variable stars. Eight out of the 14 are RR…
The nature of type II Cepheids and anomalous Cepheids is still not well known and their evolutionary channels leave many unanswered questions. We use complete collection of classical pulsating stars in the Magellanic Clouds discovered by…
We describe variable stars found in the data collected during the OGLE-III Shallow Survey covering the I-band magnitude range from 9.7 mag to 14.5 mag. The main result is the extension of period--luminosity relations for Cepheids up to 134…
We present 100 multiple cluster candidates selected from the OGLE catalog of star clusters in the Large Magellanic Cloud. Statistical analysis shows that the significant fraction of these objects may constitute physical systems. Coeval ages…
In the second part of the OGLE-III Catalog of Variable Stars (OIII-CVS) we present 197 type II Cepheids and 83 anomalous Cepheids in the Large Magellanic Cloud (LMC). The sample of type II Cepheids consists of 64 BL Her stars, 96 W Vir…
We present the results of a search for variable stars in a 26x39 arcmin^2 field around globular cluster M79 (NGC1904). The search was made by means of an extended version of image subtraction, which allows to analyze in a uniform manner CCD…