Related papers: Recurrent starspot activity and differential rotat…
Using high-precision photometry from the \textit{Kepler} mission, we investigate patterns of spot activity on the K1-type subgiant component of KIC 11560447, a short-period late-type eclipsing binary. We tested the validity of maximum…
The Kepler target KIC 5110407, a K-type star, shows strong quasi-periodic light curve fluctuations likely arising from the formation and decay of spots on the stellar surface rotating with a period of 3.4693 days. Using an established…
We present an analysis of the starspot evolution, the surface differential rotation (SDR), the correlation between chromospheric activity indicators and the spatial connection between chromospheric and photospheric activities on the active…
We present spectroscopic and photometric analysis of KIC\,9451096, where the latter is based on very high precision long cadence photometry obtained by $Kepler$ space craft. Combined spectroscopic and photometric modeling show that the…
Context. Kepler-17 is a G2V sun-like star accompanied by a transiting planet with a mass of ~2.5 Jupiter masses and an orbital period of 1.486 d, recently discovered by the Kepler space telescope. This star is highly interesting as a young…
HD 208472 is among the most active RS~CVn binaries with cool starspots. Decade-long photometry has shown that the spots seem to change their longitudinal appearance with a period of about six years, coherent with brightness variations. Our…
Making use of the data obtained from Kepler satellite, we have analysed an F-type ultra-fast rotator KIC 6791060. We derive a rotational period of 0.34365$\pm$0.00004 d. Multiple periodicity with a period separation of $\sim$0.00016 d was…
Starspots and their movements on stellar surfaces enable investigating the mechanisms of stellar magnetic activity. Information on the spot distribution and differential rotation provide important constraints for the behaviour of stellar…
We present a series of 9 Doppler images of the magnetically active K component of the RS CVn-type binary SZ Psc, based on the high-resolution spectroscopic data collected from 2014 to 2018. We apply least-squares deconvolution to all…
This paper presents the detection of a periodic dimming event in the lightcurve of the G1.5IV-V type star KIC 1718360. This is based on visible-light observations conducted by both the TESS and Kepler space telescopes. Analysis of the data…
We present surface spot maps of the K2V primary star in the pre-cataclysmic variable binary system, V471 Tau. The spot maps show the presence of large high latitude spots located at the sub-white dwarf longitude region. By tracking the…
We present photometric spot modeling of the nearly four-year long light-curve of the Kepler target KIC 5955122 in terms of persisting dark circular surface features. With a Bayesian technique, we produced a plausible surface map that shows…
We report on a new method for tracking the phases of the orbital modulations in very short-period, near-contact, and contact binary systems systems in order to follow starspots. We apply this technique to Kepler light curves for 414 binary…
We explore the connection between starspots and plages of three main-sequence stars by studying the chromospheric and photospheric activity over several rotation periods. We present simultaneous photometry and high-resolution ($R\sim…
We present the first orbital elements for the massive close binary, HD 101131, one of the brightest objects in the young, open cluster, IC 2944. This system is a double-lined spectroscopic binary in an elliptical orbit with a period of…
The spotted detached eclipsing binary (DEB) offers insights into starspots on the binary. Three spotted DEBs, KIC 8097825, KIC 6859813, and KIC 5527172, which were observed by the Kepler photometry and LAMOST spectroscopy, are studied in…
We present a spectroscopic/photometric analysis of the rapid rotator KIC8429280, discovered by ourselves as a very young star and observed by the Kepler mission. We use spectroscopic/photometric ground-based data to derive stellar…
KIC 5359678 is a 6.231-d period F-type eclipsing binary system whose component stars both show starspot activity. It was observed by the Kepler satellite in long cadence for the full four-year duration of the mission. Wang et al (2021)…
Comprehensive analysis of optical spectroscopy and space photometry of the solar type eclipsing binary system KIC\,4832197 is presented. The system is composed of F7V + F9V components with masses of $M_{1}=1.16\pm0.12~M_{\odot}$,…
We present results regarding the longitudinal migrations of cool stellar spots that exhibit remarkable oscillations and explore their possible causes. We conducted analyses using high-quality data from nine target systems of various…