Related papers: NGC 2419: an "intergalactic wanderer" or a simple …

We present the detection of RR Lyrae variable stars in the field of the Sagittarius II (Sgr II) ultra-faint dwarf (UFD) galaxy. Using B, V time-series photometry obtained with the Korea Microlensing Telescope Network (KMTNet) 1.6 m…

A search for variable stars in the globular cluster NGC 288 was carried out using a time-series of CCD images in the $V$ and $I$ filters. The photometry of all stellar sources in the field of view of our images, down to $V\approx19$ mag,…

NGC 6388 and NGC 6441 are anomalies among Galactic globular clusters in that they cannot be readily place into either Oosterhoff group I or Oosterhoff group II despite their significant numbers of RR Lyrae variables. The mean pulsation…

(Abridged) We present the results of a new search for variable stars in the Local Group (LG) isolated dwarf galaxy IC1613, based on 24 orbits of F475W and F814W photometry from the ACS camera onboard the HST. We detected 259 candidate…

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…

We report on the discovery of eleven multimode SX Phoenicis--type blue stragglers in the field of the southern globular cluster NGC 3201. In these variables both radial and non-radial modes are excited. For three variables the derived…

NGC 2808 is a unique globular cluster with not only a bimodal-horizontal branch (HB) but also with gaps on the blue horizontal branch. Adequate interpretation of the nature of the detected peculiarities in "bimodal" and "gap" clusters is of…

Messier 15 (NGC 7078) is an old and metal-poor post core-collapse globular cluster which hosts a rich population of variable stars. We report new optical ($gi$) and near-infrared (NIR, $JK_s$) multi-epoch observations for 129 RR Lyrae, 4…

The field of the globular cluster M22 (NGC 6656) was monitored between 2000 and 2008 in a search for variable stars. $BV$ light curves were obtained for 359 periodic, likely periodic, and long-term variables, 238 of which are new…

New B, V, I photometry was obtained for a sample of 152 variables (125 RR Lyrae's, 4 anomalous Cepheids, 11 classical Cepheids, 11 eclipsing binaries and a delta Scuti star) in two regions near the bar of the Large Magellanic Cloud (LMC).…

We present a CCD survey of variable stars in the Draco dwarf spheroidal galaxy. This survey, which has the largest areal coverage since the original variable star survey by Baade & Swope, includes photometry for 270 RR Lyrae stars, 9…

Time-series CCD photometric observations of the intermediate-age open cluster NGC 2099 were performed to search for variable stars. We also carried out BV photometry to study physical properties of variables in the cluster. Using V-band…

We present the results of a photometric survey for variable stars in the nearby globular cluster M5. A 14.8x22.8 arcmin^2 field centered on the cluster was monitored for a total of 37 hours with a CCD camera mounted on the 1.0-m Swope…

We made a survey of the variable stars in a $13.2 \times 13.2$ arcmin$^2$ centered on the field of the Galactic bulge cluster NGC 6558. A total of 78 variables was found in the field of the cluster. Many of these variables are included in…

We present a CCD $VI$ time-series analysis of the globular cluster NGC 6139 and its variable star population. Using the astrometric data available in $Gaia$-DR3 we performed a membership analysis that enabled the construction of a clean…

We present new $BVI$ CCD photometry for variables in the globular cluster M15. Our photometry was obtained using both the image subtraction package ISIS and DAOPHOT/ALLFRAME. The data were acquired in 2001 on two observing runs on 11…

We have undertaken a search for variable stars in the metal-rich globular cluster NGC 6388 using time-series BV photometry. Twenty-eight new variables were found in this survey, increasing the total number of variables found near NGC 6388…

We present the first CCD photometric observations of the northern open cluster NGC 2126. Data were taken on eight nights in February and December 2002 with a total time span of ~57 hours. Almost 1000 individual V-band frames were examined…

Globular clusters are both primary fossils of galactic evolution and formation and are ideal laboratories for constraining the evolution of low-mass and metal-poor stars. RR Lyrae and type II Cepheid variables are low-mass, radially…

We conducted a variable star search on the metal-rich Galactic globular cluster NGC 6652 using archival Gemini-S/GMOS data. We report the discovery of nine new variable stars in the NGC 6652 field, of which we classify six as eclipsing…