Related papers: Possible dwarf nova on the Digitized Sky Survey pl…
We initiated digitization of the Moscow collection of astronomical plates using flatbed scanners. Techniques of photographic photometry of the digital images were applied, enabling an effective search for new variable stars. Our search for…
A CCD photometry of the dwarf nova MASTER OT J172758.09 +380021.5 was carried out in 2019 during 134 nights. Observations covered three superoutbursts, five normal outbursts and quiescence between them. The available ASASSN and ZTF data for…
Two recently discovered variable stars (CzeV134 = GSC 3682 0018 = USNO-A2.0 1425-1870026 and CzeV135 = GSC 3682 2051 = USNO-A2.0 1425-1825909 = V1094 Cas), which have been identified in the field of the W UMa variable star BS Cas, are…
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 present new version of the OGLE-II catalog of eclipsing binary stars detected in the Small Magellanic Cloud, based on Difference Image Analysis catalog of variable stars in the Magellanic Clouds containing data collected from 1997 to…
The $13.6\times 13.6$ arcmin$^{2}$ field covering the central part of the globular cluster NGC~6397 was surveyed in a search for short-period variable stars. We obtained light curves for 6 close binaries, 2 SX~Phe stars and 1 RR~Lyrae…
We describe here results of a photometric time-sequence survey of the globular cluster M3 (NGC 5272), in a search for contact and detached eclipsing binary stars. We have discovered only one likely eclipsing binary and one SX Phe type star…
Three fields located close to the center of the globular cluster Omega Cen were surveyed in a search for variable stars. We present V-band light curves for 32 periodic variables. This sample includes 10 SX Phe stars, 19 eclipsing binaries,…
The central area of the Sculptor dwarf galaxy was surveyed for variable stars as a side-program of the OGLE project. Light curves in the V band were obtained for 226 RR Lyr stars and for 3 anomalous cepheids. One previously unknown…
We report spectroscopic observations of seven bright southern cataclysmic variable stars, collected on a single two-week observing run using the 1.9-m Radcliffe telescope at the South African Astronomical Observatory. We used radial…
This work is dedicated to the discovery of the eclipsing variable star Grigoriev 1 and determining the parameters of its binary system. The star was found through the systematic checking of ultraviolet sources of GALEX space observatory in…
We present the fifth part of the OGLE Catalog of Periodic Variable Stars in the Galactic bulge. 574 variable stars: 44 pulsating, 369 eclipsing and 161 miscellaneous type were detected in four fields located symmetrically in galactic…
The cataclysmic variable V893 Sco is an eclipsing dwarf nova which, apart from outbursts with comparatively low amplitudes, exhibits a particularly strong variability during quiescence on timescales of days to seconds.The present study aims…
We present the results of a radial velocity (RV) survey of 14 brown dwarfs (BDs) and very low-mass (VLM) stars in the Upper Scorpius OB association (UScoOB) and 3 BD candidates in the rho Ophiuchi dark cloud core. We obtained…
We report on detection of negative superhumps in KR Aur which is the representative member of the VY Scl stars. The observations were obtained with the multi-channel photometer during 107 h. The analysis of the data clearly revealed…
The Be star \delta\ Scorpii is an interesting binary system, whose primary companion created a circumstellar disk after the periastron passage of the secondary in 2000, being since then classified as Be. This work presents the results of a…
We report the discovery of two new short-period variable stars in the Lyra constellation, GSC2.3 N208000326 and GSC2.3 N20B000251, observed at the Astronomical Observatory of Autonomous Region of the Aosta Valley. Photometric measurements…
We present the AGAPE astrometric and photometric catalogue of 1579 variable stars in a 14'x10' field centred on M31. This work is the first survey devoted to variable stars in the bulge of M31. The R magnitudes of the objects and the B-R…
We present the discovery of a plausible super-luminous supernova (SLSN), found in the archival data of Sloan Digital Sky Survey (SDSS) Stripe 82, called PSN 000123+000504. The supernova peaked at M_g<-21.3 mag in the second half of…
Nova Sagittarii 1943 (V1148 Sgr) was an 8th-mag optical transient that was unusual in having a late-type spectrum during its outburst, in striking contrast to the normal high-excitation spectra seen in classical novae. Unfortunately, only…