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Related papers: Activity cycles in RS CVn type stars

200 papers

We have acquired high-resolution echelle spectra of 225 F6-M5 type stars in the southern hemisphere. The stars are targets or candidates to be targets for the Anglo-Australian Planet Search. CaII HK line cores were used to derive activity…

Rotation is a directly-observable stellar property, and drives magnetic field generation and activity through a magnetic dynamo. Main sequence stars with masses below approximately 0.35Msun (mid-to-late M dwarfs) are fully-convective, and…

We present a catalogue of rotation and chromospheric activity in a sample of 334 M dwarfs of spectral types M0--M4.5 populating the parameter space around the boundary to full convection. We obtained high-resolution optical spectra for 206…

Solar and Stellar Astrophysics · Physics 2015-06-03 Ansgar Reiners , Nandan Joshi , Bertrand Goldman

M-type stars are crucial for stellar activity studies since they cover two types of magnetic dynamos and particularly intriguing for habitability studies due to their abundance and long lifespans during the main-sequence stage. In this…

Solar and Stellar Astrophysics · Physics 2024-03-28 Xue Li , Song Wang , Henggeng Han , Huiqin Yang , Chuanjie Zheng , Yang Huang , Jifeng Liu

We measure the rotation periods of 19 stars in the {\it Kepler} transiting planetary systems, $P_{\rm rot, astero}$ from asteroseismology and $P_{\rm rot, phot}$ from photometric variation of their lightcurve. Two stars exhibit two clear…

Earth and Planetary Astrophysics · Physics 2019-04-17 Yasushi Suto , Shoya Kamiaka , Othman Benomar

We present the results of a long-term monitoring campaign of the H\alpha line in a sample of bright OB-supergiants (O7.5-B9) that aims at detecting rotationally modulated changes potentially related to the existence of large-scale wind…

Astrophysics · Physics 2009-11-10 T. Morel , S. V. Marchenko , A. K. Pati , K. Kuppuswamy , M. T. Carini , E. Wood , R. Zimmerman

Photospheric stellar activity might be an important source of noise and confusion in the radial-velocity measurements. RV planet search surveys as well as follow-up of photometric transit surveys require a deeper understanding and…

Earth and Planetary Astrophysics · Physics 2015-03-17 I. Boisse , F. Bouchy , G. Hebrard , X. Bonfils , N. C. Santos , S. Vauclair

We investigate the activity induced signals related to rotation in late type stars (FGKM). We analyse the Ca II H&K, the H alpha and the radial velocity time-series of 55 stars using the spectra from the HARPS public database and the…

Earth and Planetary Astrophysics · Physics 2017-05-31 A. Suárez Mascareño , R. Rebolo , J. I. González Hernández , M. Esposito

The All Sky Automated Survey (ASAS) monitors bright stars (8 mag < V < 14 mag) south of declination +28 deg. The ASAS Catalogue of Variable Stars (ACVS) presently contains 50,099 objects; among them are 2212 objects classified as RR Lyrae…

Astrophysics · Physics 2008-11-26 D. M. Szczygiel , D. C. Fabrycky

We present updated results from the ongoing XMM-Newton monitoring program of moderately active, solar-like stars to investigate stellar X-ray activity cycles; here we report on the binary systems Alpha Cen A/B and 61 Cyg A/B. For 61 Cyg A…

Astrophysics · Physics 2007-05-23 J. Robrade , J. H. M. M. Schmitt , A. Hempelmann

Our aim is to investigate the tidal interaction in High-mass X-ray Binaries and Symbiotic stars in order to determine in which objects the rotation of the mass donors is synchronized or pseudosynchronized with the orbital motion of the…

Solar and Stellar Astrophysics · Physics 2014-08-27 Kiril Stoyanov , Radoslav Zamanov

We carry out an analysis of the Mg II 2796.34 A emission line in RS CVn stars and make a comparison with the normal stars studied in a previous paper (Paper I). The sample of RS CVn stars consists of 34 objects with known HIPPARCOS…

Astrophysics · Physics 2009-11-10 D. Cardini , A. Cassatella , M. Badiali , A. Altamore , M. J. Fernandez-Figueroa

The photospheric spot activity of some of the stars with transiting planets discovered by the CoRoT space experiment is reviewed. Their out-of-transit light modulations are fitted by a spot model previously tested with the total solar…

Solar and Stellar Astrophysics · Physics 2015-05-20 A. F. Lanza

Kepler ultra-high precision photometry of long and continuous observations provides a unique dataset in which surface rotation and variability can be studied for thousands of stars. Because many of these old field stars also have…

Context. The IUE database provides a large number of UV high and low-resolution spectra of RS CVn-type stars from 1978 to 1996. In particular, many of these stars were monitored continuously during several seasons by IUE. Aims. Our main…

Astrophysics · Physics 2009-02-13 Andrea P. Buccino , Pablo J. D. Mauas

Like the solar cycle, stellar activity cycles are also irregular. Observations reveal that rapidly rotating (young) Sun-like stars exhibit a high level of activity with no Maunder-like grand minima and rarely display smooth regular activity…

Solar and Stellar Astrophysics · Physics 2023-05-10 Vindya Vashishth , Bidya Binay Karak , Leonid Kitchatinov

The CoRoT satellite has made available high precision photometric observations of a large number of stars of different spectral types. Continuous photometric time series allow the characterization of stellar microvariability in a systematic…

Solar and Stellar Astrophysics · Physics 2015-03-19 J. C. Hulot , F. Baudin , R. Samadi , M. J. Goupil

We investigate the relationship between age and chromospheric activity for 139 M dwarf stars in wide binary systems with white dwarf companions. The age of each system is determined from the cooling age of its white dwarf component. The…

Astrophysics · Physics 2009-11-10 Nicole M. Silvestri , Suzanne L. Hawley , Terry D. Oswalt

Stellar rotation is a fundamental observable that drives different aspects of stellar and planetary evolution. In this work, we present an unprecedented manifold analysis of 160 B-type stars with light curves collected by the TESS space…

We present results of our analysis of up to 15 years of photometric data from eight AM CVn systems with orbital periods between 22.5 and 26.8 min. Our data has been collected from the GOTO, ZTF, Pan-STARRS, ASAS-SN and Catalina all-sky…