Related papers: Variable stars in the globular cluster M28 (NGC 66…
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 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 results of the search for variable stars in the field of young open cluster NGC 581. Based on 19 nights of observations, 6 new variable stars were discovered. Two of them turned out to be eclipsing binary systems. Another two…
We report an analysis of new $V$ and $I$ CCD time-series photometry of the distant globular cluster NGC 6229. The principal aims were to explore the field of the cluster in search of new variables, and to Fourier decompose the RR Lyrae…
We present the results of a variable stars search in the field of the old open cluster NGC 2204. Five new variables were found, four of them being eclipsing binaries. The sample includes a detached binary located at the turnoff, a W UMa -…
We present the results of a photometric study of RR Lyrae variables in the field of the globular cluster M55. We have discovered nine new RR Lyrae stars, increasing the number of known variables in this cluster to 15 objects. Five of the…
The field of the globular cluster M12 (NGC 6218) was monitored between 1995 and 2009 in a search for variable stars. $BV$ light curves were obtained for 36 periodic or likely periodic variables. Thirty-four of these are new detections.…
The purpose of this paper is to show that RR Lyrae variables exist and can be detected in M31 globular clusters. We report on the first tentative identification of RR Lyrae candidates in four globular clusters of the Andromeda galaxy, i.e.…
We present the results of the $UBVI_C$ variability survey in the young open cluster NGC 6611 based on observations obtained during 34 nights spanning one year. In total, we found 95 variable stars. Most of these stars are classified as…
This work presents the charge-coupled device (CCD) photometric survey of the old open cluster NGC 188. Time-series V-band photometric observations were conducted for ten nights in January 2017 using the Nanshan One-meter Wide-field…
We present new B, V and I CCD time-series photometry for 177 variable stars in a 13'X 13' field centered on the globular cluster M54 (lying at the center of the Sagittarius dwarf spheroidal galaxy), 94 of which are newly identified…
We present a variable star catalog of an extensive ground-based wide-field variability survey in the globular cluster omega Centauri. Using the ANU 40-inch (1m) telescope at Siding Spring Observatory, the cluster was observed with a 52'x52'…
We have investigated the variable stars in the field surrounding NGC 2355 based on the time-series photometric observation data. More than 3000 CCD frames were obtained in the V band spread over 13 nights with the Nanshan One-meter…
We present a comprehensive catalog of 2824 RR Lyrae stars (RRLs) residing in 115 Galactic globular clusters (GCs). Our catalog includes 1594 fundamental-mode (RRab), 824 first-overtone (RRc), and 28 double-mode (RRd) RRLs, as well as 378…
We report evidence for a new class of variable star, which we dub millimagnitude RR Lyrae (mmRR). From K2 observations of the globular cluster M4, we find that out of 24 horizontal branch stars not previously known to be RR Lyrae variables,…
We present a long-term project aimed at completing the census of (bright) variable stars in Galactic globular clusters. While our main aim is to obtain a reliable assessment of the populations of RR Lyrae and type II Cepheid stars in the…
We present the results of our search for variable stars in the intermediate-age open cluster NGC 7789. We have found 45 variable stars: 35 eclipsing binaries, five pulsating variables and five miscellaneous variables. Most of the eclipsing…
In this paper, we report the detections of stellar variabilities from the first 2-year observations of sky area of about 1300 square degrees from the Tsinghua University-NAOC Transient Survey (TNTS). A total of 1237 variable stars…
The field of the globular cluster NGC 6362 was monitored between 1995 and 2009 in a search for variable stars. BV light curves were obtained for 69 periodic variables including 34 known RR Lyr stars, 10 known objects of other types and 25…
We present results of a search for variable stars in a region of the globular cluster NGC 4147 based on photometric observations with 4k x 4k CCD imager mounted at the axial port of the recently installed 3.6 m Devasthal optical telescope…