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Related papers: Stellar differential rotation from direct starspot…

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Context. There exist few variability studies of stars in the region in the Hertzsprung-Russell diagram between the A and B-star pulsational instability strips. With the aid of the high precision continuous measurements of the CoRoT space…

Solar and Stellar Astrophysics · Physics 2015-05-30 P. Degroote , B. Acke , R. Samadi , C. Aerts , D. W. Kurtz , A. Noels , A. Miglio , J. Montalban , S. Bloemen , A. Baglin , F. Baudin , C. Catala , E. Michel , M. Auvergne

We present measurements of the rotation rates of individual starspots on the rapidly rotating young K0 dwarf AB Doradus, at six epochs between 1988 December and 1996 December. The equatorial rotation period of the star decreased from 0.5137…

Astrophysics · Physics 2009-11-07 A. Collier Cameron , J. -F. Donati

Asteroseismology has undergone a profound transformation as a scientific field following the CoRoT and Kepler space missions. The latter is now yielding the first measurements of latitudinal differential rotation obtained directly from…

Solar and Stellar Astrophysics · Physics 2019-03-27 M. Bazot , O. Benomar , J. Christensen-Dalsgaard , L. Gizon , S. Hanasoge , M. Nielsen , P. Petit , K. R. Sreenivasan

We first reported evidence for differential rotation of Kappa1 Ceti in Paper I. In this paper we demonstrate that the differential rotation pattern closely matches that for the Sun. This result is based on additional MOST (Microvariability…

Context. The relation between solar surface rotation and sunspot activity still remains open. Sunspot activity has dramatically reduced in solar cycle 24 and several solar activity indices and flux measurements experienced unprecedentedly…

Solar and Stellar Astrophysics · Physics 2015-02-18 L. Zhang , K. Mursula , I. Usoskin

We continue our studies on stellar latitudinal differential rotation. The presented work is a sequel of the work of Reiners et al. who studied the spectral line broadening profile of hundreds of stars of spectral types A through G at high…

Solar and Stellar Astrophysics · Physics 2010-10-29 Matthias~Ammler von Eiff , Ansgar Reiners

We investigate differential rotation in rapidly rotating solar-type stars by means of an axisymmetric mean field model that was previously applied to the sun. This allows us to calculate the latitudinal entropy gradient with a rea- sonable…

Solar and Stellar Astrophysics · Physics 2015-05-28 Hideyuki Hotta , Takaaki Yokoyama

We present projected rotational velocities and new measurements of the rotational profile of some 180 nearby stars with spectral types A-F. The overall broadening profile is derived analysing spectral line shape from hundreds of spectral…

Solar and Stellar Astrophysics · Physics 2015-06-04 Matthias Ammler-von Eiff , Ansgar Reiners

We analyzed the sunspot-group daily data that were reported by Greenwich Photoheliogrphic Results (GPR) during the period 1874-1976 and Debrecen Photoheliographic Data (DPD) during the period 1977-2017. We determined the equatorial rotation…

Solar and Stellar Astrophysics · Physics 2020-12-04 J. Javaraiah

Radial differential rotation is an important factor in stellar dynamo theory. In the Sun, helioseismology has revealed a near surface shear layer in the upper 5 to 10% of the convection zone. At low to midlatitudes, the rotation velocity…

Solar and Stellar Astrophysics · Physics 2025-10-15 T. Corbard , M. Faurobert , B. Gelly , R. Douet , D. Laforgue

The surface differential rotation of active solar-type stars can be investigated by means of Doppler and Zeeman-Doppler Imaging, both techniques enabling one to estimate the short-term temporal evolution of photospheric structures (cools…

Astrophysics · Physics 2009-11-10 P. Petit , J. -F. Donati , A. Collier Cameron

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

The sunspot position from Greenwich Photoheliographic Results (GPR), US Air Force Solar Optical Observing Network and National Oceanic and Atmospheric Administration (USAF/NOAA), and Debrecen Photoheliographic Data (DPD) data bases in the…

Solar and Stellar Astrophysics · Physics 2017-12-20 Domagoj Ruždjak , Roman Brajša , Davor Sudar , Ivica Skokić , Ivana Poljančić Beljan

We investigate the temporal spot evolution of the K-giant component in the RS CVn-type binary system $\zeta$\,Andromedae to establish its surface differential rotation. Doppler imaging is used to study three slightly overlapping…

Solar and Stellar Astrophysics · Physics 2015-06-03 Zs. Kővári , H. Korhonen , L. Kriskovics , K. Vida , J. -F. Donati , H. Le Coroller , J. D. Monnier E. Pedretti , P. Petit

From high-precision MOST photometry spanning 35 days the existence of two spots rotating with slightly differing periods is confirmed. From the marginal probability distribution of the derived differential rotation parameter k its…

Astrophysics · Physics 2009-11-13 H. -E. Froehlich

Doppler Imaging of starspots on young solar analogues is a way to investigate the early history of solar magnetic activity by proxy. Doppler images of young G-dwarfs have yielded the presence of large polar spots, extending to moderate…

Solar and Stellar Astrophysics · Physics 2015-06-17 Carolyn Brown , Brad Carter , Stephen Marsden , Ian Waite

This paper reports positive detections of surface differential rotation on two rapidly rotating cool stars at several epochs, by using stellar surface features (both cool spots and magnetic regions) as tracers of the large scale latitudinal…

Astrophysics · Physics 2009-11-10 J. -F. Donati , A. Collier Cameron , P. Petit

Differential rotation can be detected in single line profiles of stars rotating more rapidly than about $v \sin{i} = 10$ km s$^{-1}$ with the Fourier transform technique. This allows to search for differential rotation in large samples to…

Astrophysics · Physics 2009-11-13 A. Reiners

With the advent of space-based precision photometry missions the quantity and quality of starspot light curves has greatly increased. This paper presents a large number of starspot models and their resulting light curves to: 1) better…

Solar and Stellar Astrophysics · Physics 2020-08-13 Gibor Basri , Riya Shah

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…

Solar and Stellar Astrophysics · Physics 2026-03-25 Mikko Tuomi , András Haris , Thomas Hackman