Related papers: PX Andromedae: Superhumps and variable eclipse dep…
Over the last decade, the pre-main sequence star KH 15D has exhibited periodic eclipses that are surprisingly deep (~3 mag) and long-lasting (~40% of the 48.4-day period). The cause of the eclipses is unknown, but it could be a feature in a…
We have obtained 48 high resolution echelle spectra of the pre-main sequence eclipsing binary system KH~15D (V582 Mon, P = 48.37 d, $e$ $\sim$ 0.6, M$_{A}$ = 0.6 M$_{\odot}$, M$_{B}$ = 0.7 M$_{\odot}$). The eclipses are caused by a…
We presents result of CDD photometry for SU UMa dwarf nova NY Her during 6 nights in June 2017 when object was in quiescence. Light curves clearly show strong amplitude variations in a range of 0m.7-1m.1. Time series analysis revealed a…
An important goal of the disk instability model is to explain the superhump phenomenon. Superhumps are features found in the light curves of binary systems, characterized by a period slightly different from the binary orbital period. In…
The massive black hole + Wolf-Rayet binary IC10 X-1 was observed in a series of 10 Chandra and 2 XMM-Newton observations spanning 2003-2012, showing consistent variability around 7 x10^37 erg/s, with a spectral hardening event in 2009. We…
This study continues our in-depth investigation of total-eclipse W Ursae Majoris-type contact binaries by analyzing eight new systems, complementing our previous work. Multiband $BVR_cI_c$ photometric data were acquired through ground-based…
We report photometry results of a frequently outbursting dwarf nova, ER Ursae Majoris. To measure the outburst parameters of the system, we carried out analyses of the light curve, periodograms, and O-C diagrams. We investigated the…
Quasi-periodic eruptions (QPEs) are rapid, recurring X-ray bursts from supermassive black holes, believed to result from interactions between accretion disks and surrounding matter. The galaxy SDSS1335+0728, previously stable for two…
We present time series UV and optical (1150 -- 8000 A) spectrophotometry of the novalike (NL) cataclysmic variable V348 Pup through and after eclipse. Outside of eclipse, the spectrum is characterized by a blue continuum, strong line…
Most ultraluminous X-ray sources (ULXs) are thought to be supercritical accreting compact objects, where massive outflows are inevitable. Using the long-term monitoring data with the Swift X-ray Telescope, we identified a common feature in…
Orbital period changes are an important diagnostic for understanding low mass X-ray binary (LMXB) accretion-induced angular momentum exchange and overall system evolution. We present our most recent results for the eclipse timing of the…
We present 7 eclipse timings of the low mass X-ray binary EXO0748-676 obtained with the USA experiment during 1999-2000 as well as 122 eclipse timings obtained with RXTE during 1996-2000. According to our analysis, the mean orbital period…
Orbital period changes of binary stars may be caused by the presence of a third massive body in the system. Here we have searched the archive of the Wide Angle Search for Planets (SuperWASP) project for evidence of period variations in…
Results are presented of a five-year project to study the orbital periods of eighteen deeply eclipsing novalike cataclysmic variables, collectively known as SW Sextantis stars, by combining new measurements of eclipse times with published…
XMM-Newton was used to observe two eclipsing, magnetic cataclysmic variables, DP Leo and WW Hor, continuously for three orbital cycles each. Both systems were in an intermediate state of accretion. For WW Hor we also obtained optical light…
We report on the X-ray observations of the eclipsing polar HY Eri (RX J0501-0359), along with its photometric, spectrophotometric, and spectropolarimetric optical variations, collected over 30 years. With an orbital period of 2.855 h, HY…
$TESS$ photometric data of LS~Cam from sectors 19, 20 and 26 are analysed. The obtained power spectra from sectors 19 and 20 show multiple periodicities - orbital variations ($P_{orb} = 0.14237$ days), slightly fluctuating superorbital…
Context: We present a new study of the eclipsing cataclysmic variable CzeV404 Her (Porb = 0.098 d) that is located in the period gap. Aims: This report determines the origin of the object and the system parameters and probes the accretion…
Context: Detecting moons around exoplanets is a major goal of current and future observatories. Moons are suspected to influence rocky exoplanet habitability, and gaseous exoplanets in stellar habitable zones could harbour abundant and…
We present the results of a simultaneous monitoring, lasting more than 2 years, of the optical and near-infrared photometric and polarimetric activity of the variable protostar PV Cep. During the monitoring period, an outburst has occurred…