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We have used spectrophotometric data from the Hubble Space Telescope to eclipse-map the primary component of the RS CVn binary SV Cam over 9 HST orbits. We find from these observations and the HIPPARCOS parallax that the surface flux in the…

We present a study of high-resolution spectra of RS Canum Venaticorum (RS CVn), a prototype of active binary systems. Our data were obtained from 1998 to 2017 using different telescopes. We analyze the chromospheric activity indicators Ca…

Solar and Stellar Astrophysics · Physics 2024-01-08 Dongtao Cao , Shenghong Gu , U. Wolter , M. Mittag , J. H. M. M. Schmitt , Dongyang Gao , Shaoming Hu

We have used maximum entropy eclipse mapping to recover images of the visual surface brightness distribution of the primary component of the RS CVn eclipsing binary SV Cam, using high-precision photometry data obtained during three primary…

Astrophysics · Physics 2009-11-11 S. V. Jeffers , J. R. Barnes , A. Collier Cameron , J. -F. Donati

We present the first Doppler images of the prototypical active binary star RS CVn, derived from high-resolution spectra observed in 2004, 2016 and 2017, using three different telescopes and observing sites. We apply the least-squares…

Solar and Stellar Astrophysics · Physics 2020-02-05 Yue Xiang , Shenghong Gu , U. Wolter , J. H. M. M. Schmitt , A. Collier Cameron , J. R. Barnes , M. Mittag , V. Perdelwitz , S. Kohl

In this paper, size distributions of starspots extrapolated from the case of the Sun, are modelled on the eclipsing binary SV Cam to synthesise images of stellar photospheres with high spot filling factors. These spot distributions pepper…

Astrophysics · Physics 2009-11-11 S. V. Jeffers

We present here the results on the physical nature a RS CVn binary KIC 7885570 and its chromospheric activity based on the Kepler Mission data. Assuming the primary component temperature, 6530 K, the temperature of the secondary component…

Solar and Stellar Astrophysics · Physics 2018-02-06 M. Kunt , H. A. Dal

We present Doppler Images of the RS CVn binary system HR 1099 (V711 Tau) from spectra taken in two different sites, KPNO and MSO, during the MUSICO S 1998 campaign. Contemporaneous APT photometry is used to constrain the Doppler Images. The…

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 $M_{1}=1.16\pm0.12~M_{\odot}$,…

Solar and Stellar Astrophysics · Physics 2023-06-21 Orkun Özdarcan , Hasan Ali Dal , Ezgi Yoldaş

EL CVn-type eclipsing binaries are composed of a massive A-type main-sequence primary star and a hotter B-type secondary star. This paper presents the time-series photometric and asteroseismic results of the EL CVn-type star 1SWASP…

Solar and Stellar Astrophysics · Physics 2021-11-03 Seung-Lee Kim , Jae Woo Lee , Chung-Uk Lee , Yongseok Lee , Dong-Joo Lee , Kyeongsoo Hong , Sang-Mok Cha , Dong-Jin Kim , Byeong-Gon Park

We present Roche tomograms of the G5-G8 IV/V secondary star in the long-period cataclysmic variable BV Cen reconstructed from MIKE echelle data taken on the Magellan Clay 6.5-m telescope. The tomograms show the presence of a number of…

Astrophysics · Physics 2009-11-13 C. A. Watson , D. Steeghs , T. Shahbaz , V. S. Dhillon

We model the photometry of RS CVn star $\sigma$ Geminorum to obtain new information on the changes of the surface starspot distribution, i.e., activity cycles, differential rotation and active longitudes. We use the previously published…

Solar and Stellar Astrophysics · Physics 2015-06-17 P. Kajatkari , T. Hackman , L. Jetsu , J. Lehtinen , G. W. Henry

This paper presents new CCD BVRI light curves of the newly discovered RS CVn eclipsing binary V1034 Her in 2009 and 2010, which shapes are different from the previous published results. They show asymmetric outside eclipse and we try to use…

Solar and Stellar Astrophysics · Physics 2013-07-01 Zhang liyun

We present multicolour photometry and modelling of the active eclipsing binary star V405 And. The components of 0.2 and 0.5 solar masses are just below and above the theoretical limit of the full convection, that is thought to be around 0.3…

Astrophysics · Physics 2010-05-18 K. Vida , K. Olah , Zs. Kovari , J. Bartus

We present observations and analysis of an RS CVn-type double-lined eclipsing binary system, RU Cnc. The system has been observed for over a century. The high-quality long-cadence \emph{Kepler} K2 C5 and C18, newly obtained observations,…

Solar and Stellar Astrophysics · Physics 2019-08-21 Kutay A. Çokluk , Dolunay Koçak , Tuğce İçli , Sinem Karaköse , Selin Üstündağ , Kadri Yakut

According to earlier Doppler images of the magnetically active primary giant component of the RS CVn binary II Peg, the surface of the star was dominated by one single active longitude that was clearly drifting in the rotational frame of…

Quantifying stellar parameters and magnetic activity for cool stars in double-lined spectroscopic binaries (SB2) is not straightforward, as both stars contribute to the observed composite spectra and are likely variable. Disentangled…

Solar and Stellar Astrophysics · Physics 2025-12-11 Ö. Adebali , M. Weber , K. G. Strassmeier , I. V. Ilyin , M. Steffen , Zs. Kovári

We present a Roche tomography reconstruction of the secondary star in the cataclysmic variable AE Aqr. The tomogram reveals several surface inhomogeneities that are due to the presence of large, cool starspots. In addition to a number of…

Astrophysics · Physics 2009-11-11 C. A. Watson , V. S. Dhillon , T. Shahbaz

We present the first Doppler images of the active eclipsing binary system SZ Psc, based on the high-resolution spectral data sets obtained in 2004 November and 2006 September--December. The least-squares deconvolution technique was applied…

Solar and Stellar Astrophysics · Physics 2015-12-23 Yue Xiang , Shenghong Gu , A. Collier Cameron , J. R. Barnes , Liyun Zhang

We present BVR observations of DK CVn from 2007 and 2008. We analysed the BVR light curves of the system and obtained the system's parameters. Using the `q-search' method, we measured the mass ratio of the system (q) as 0.55. Taking the…

Solar and Stellar Astrophysics · Physics 2012-06-26 H. A. Dal , E. Sipahi , O. Özdarcan

We present new V-band differential brightness measurements as well as new radial-velocity measurements of the detached, circular, 0.84-day period, double-lined eclipsing binary system CV Boo. These data along with other observations from…

Astrophysics · Physics 2009-11-13 Guillermo Torres , Luiz Paulo R. Vaz , Claud H. Sandberg Lacy
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