Related papers: Spectral Identification of the u-band Variable Sou…

We report the detection of variable stars within a 11.5' x 11.5' region near the Galactic centre (GC) that includes the Arches and Quintuplet clusters, as revealed by the VISTA Variables in the Via Lactea (VVV) survey. There are 353 sources…

We report the results of a diffraction-limited, photometric variability study of the central 5"x5" of the Galaxy conducted over the past 10 years using speckle imaging techniques on the W. M. Keck I 10 m telescope. Within our limiting…

We present results of star variability analysis in OGLE II first bulge field. Photometric database was derived by means of image subtraction method (Wozniak 2000) and contains 4597 objects pre-classified as variables. We analyzed all the…

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,…

Sloan Digital Sky Survey (SDSS) repeat spectroscopic observations have resulted in multiple-epoch spectroscopy for roughly 2500 quasars observed more than 50 days apart. From this sample, we identify 315 quasars that have varied…

We have discovered six galaxies with spectroscopically confirmed redshifts of 4.8<z<5.8 in a single 44 square arcminute field imaged deeply in R, I and z-bands. All the spectra show an emission-line in the region around 7000-8400 angstroms…

We present the quasar catalog from Data Releases 10 to 12 of the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) Quasar Survey, comprising quasars observed between September 2021 and June 2024. We robustly identified…

Results of a search for variable stars in the central region of the globular cluster M13 are presented. Prior to this study, 36 variable and suspected variable stars were known in this cluster (Osborn 2000; Clement et al. 2001). Of these…

We report on I band photometric observations of 21 stars with spectral types between M8 and L4 made using the Isaac Newton Telescope. The total amount of time for observations which had a cadence of <2.3 mins was 58.5 hrs, with additional…

We take advantage of the Gaia data release 2 to present 275 and 1,774 ultraviolet luminous stars in the FUV and the NUV. These stars are 5$\sigma$ exceeding the centers of the reference frame that is built with over one million UV stars in…

A sample of Cataclysmic Variables (CVs) is presented including spectroscopically identified 380 spectra of 245 objects, of which 58 CV candidates are new discoveries. The BaggingTopPush and the Random Forest algorithms are applied to the…

We present results of variability search in the field of the young open cluster NGC 1502. Eight variable stars were discovered. Of six other stars in the observed field that were suspected for variability, we confirm variability of two,…

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).…

Using archival observations recorded over a 5+ year timeframe with the NASA Galaxy Evolution Explorer (GALEX) satellite, we present a study of the ultraviolet (UV) variability of 4360 quasars of redshifts up to z=2.5 that have optical…

We report on the initial results of a spectroscopic investigation of galaxies in the Hubble Deep Field which exhibit spectral discontinuities between the F450W and F300W passbands, indicative of the presence of the Lyman continuum break in…

We present a search and analysis of variable stars in the recently discovered Crater~II dwarf galaxy. Based on $B$, $V$, $I$ data collected with the Isaac Newton Telescope (FoV$\sim$0.44 square degrees) we detected 37 variable stars, of…

Based on a comparison of the SRG/eROSITA catalog of X-ray active stars and the Gaia catalog, a sample of 502 peculiar objects was obtained for which Gaia, on one hand, detects statistically significant values of parallax or proper motion…

We present initial results of the first panoramic search for high-amplitude near-infrared variability in the Galactic Plane. We analyse the widely separated two-epoch K-band photometry in the 5th and 7th data releases of the UKIDSS Galactic…

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…

Utilizing a decade-long unTimely dataset, supplemented by multi-band data from archives, we search for young stellar objects (YSOs) with variations larger than one magnitude in W1 band within a region of 110 square degrees in the Galactic…