English
Related papers

Related papers: Characterising the stellar differential rotation b…

200 papers

The main aim of this work is to determine the solar differential rotation by tracing sunspot groups during the period 1964-2016, using the Kanzelh\"ohe Observatory for Solar and Environmental Research (KSO) sunspot drawings and white light…

Surface brightness maps for the young K0 dwarf AB Doradus are reconstructed from archival data sets for epochs spanning 1988 to 1994. By using the signal-to-noise enhancement technique of Least-Squares Deconvolution, our results show a…

Astrophysics · Physics 2009-09-29 S. V. Jeffers , J. -F. Donati , A. Collier Cameron

A multifractal formalism is employed to analyse high-precision time-series data of \textit{Kepler} stars with surface differential rotation traces. The multifractal detrended moving average analysis (MFDMA) algorithm has been explored to…

Solar and Stellar Astrophysics · Physics 2019-08-07 D. B. de Freitas , M. M. F. Nepomuceno , J. G. Cordeiro , M. L. Das Chagas , J. R. De Medeiros

We present the first measurements of surface differential rotation on a pre-main sequence binary system. Using intensity (Stokes I) and circularly polarised (Stokes V) timeseries spectra, taken over eleven nights at the Anglo-Australian…

Frequency analysis of long-term ultra-precise photometry can lead to precise values of rotation frequencies of rotating stars with ``hump and spike'' features in their periodograms. Using these features, we computed the rotation frequencies…

Solar and Stellar Astrophysics · Physics 2021-04-27 Otto Trust , Edward Jurua , Peter De Cat , Santosh Joshi

CoRoT-2, the second planet-hosting star discovered by the CoRoT satellite, is a young and active star. A total of 77 transits were observed for this system over a period of 135 days. Small modulations detected in the optical light curve of…

Solar and Stellar Astrophysics · Physics 2015-05-27 Adriana Silva-Valio , A. F. Lanza

We reanalyzed high quality spectra of 158 stars of spectral types A0--F1 and $v \sin{i}$ between 60 and 150 km s$^{-1}$. Using a Least Squares Deconvolution technique we extracted high $S/N$ broadening profiles and determined the loci of…

Astrophysics · Physics 2009-11-10 A. Reiners , F. Royer

Stellar magnetic activity is governed by the interplay between rotation, convection, and the evolution of surface magnetic structures, yet the role of planetary systems in shaping these processes remains uncertain. Here, we analyze…

Solar and Stellar Astrophysics · Physics 2026-05-27 Alexandre Araújo , Adriana Valio

HD 129929 is a slowly-rotating $\beta$ Cephei pulsator with a rich spectrum of detected oscillations, including two rotational multiplets. The asteroseismic interpretation revealed the presence of radial differential rotation in this…

Solar and Stellar Astrophysics · Physics 2022-08-03 Sébastien Salmon , Facundo Moyano , Patrick Eggenberger , Lionel Haemmerlé , Gaël Buldgen

We present the results of three-dimensional simulations of the deep convective envelope of a young (10 Myr) one-solar-mass star, obtained with the Anelastic Spherical Harmonic code. Since young stars are known to be faster rotators than…

Astrophysics · Physics 2008-04-03 Jérôme Ballot , Allan Sacha Brun , Sylvaine Turck-Chièze

The differential rotation of the F5V-IV star Procyon A is computed for a class of models which are consistent with recent astrometric and asteroseismic data. The rotation pattern is determined by solving the Reynolds equation for motion,…

Astrophysics · Physics 2008-11-26 A. Bonanno , M. Kueker , L. Paterno'

We present 23 Doppler images of the spotted RS CVn star HR 1099 from 1981 to 1992. HR 1099 shows a large cool polar spot which has persisted for the 11 years of this study and other low-latitude spots which come and go on relatively short…

Astrophysics · Physics 2007-05-23 Steven S. Vogt , Artie P. Hatzes , Anthony A. Misch , M. Kurster

Neutron stars may experience differential rotation on short, dynamical timescales following extreme astrophysical events like binary neutron star mergers. In this work, the masses and radii of differentially rotating neutron star models are…

Nuclear Theory · Physics 2023-11-16 Delaney Farrell , Fridolin Weber , Jia Jie Li , Armen Sedrakian

Four months of quasi-simultaneous spectroscopic and photometric observations were used to study the variations of the photometric light curve, the evolution of the chromospheric activity from the H$\alpha$ and H$\beta$ lines, and the…

Solar and Stellar Astrophysics · Physics 2017-01-11 M. Flores Soriano , K. G. Strassmeier

The lower part of the classical instability strip and the surrounding main sequence are populated by a large variety of pulsating variable stars. In the past years a great effort was made by the stellar group of Brera Observatory to collect…

Astrophysics · Physics 2007-05-23 Ennio Poretti

In the last years, space missions such as COROT, Kepler or MOST have provided very accurate photometric observational data. In the particular case of $\delta$ Scuti stars, the observed frequency spectra have hundreds (if not thousands) of…

Solar and Stellar Astrophysics · Physics 2015-03-13 A. Moya , A. García Hernández , J. -C. Suárez , C. Rodríguez-López , R. Garrido

Measuring surface differential rotation (DR) on different types of stars is important when characterizing the underlying stellar dynamo. It has been suggested that anti-solar DR laws can occur when strong meridional flows exist. We aim to…

Solar and Stellar Astrophysics · Physics 2016-08-10 G. Harutyunyan , K. G. Strassmeier , A. Künstler , T. A. Carroll , M. Weber

Increasing evidence is becoming available about not only the surface differential rotation of rapidly rotating cool stars but, in a small number of cases, also about temporal variations, which possibly are analogous to the solar torsional…

Astrophysics · Physics 2009-11-10 E. Covas , D. Moss , R. Tavakol

Context. The study of young solar type stars is fundamental for a better understanding of the magnetic activity of the Sun. As a planet in transit crosses in front of its host star, a darkspot on the stellar surface may be occulted, causing…

Solar and Stellar Astrophysics · Physics 2020-03-11 Yuri Netto , Adriana Valio

The observed amplitude of the rotational photometric modulation of a star with spots should depend on the inclination of its rotational axis relative to our line of sight. Therefore, the distribution of observed rotational amplitudes of a…

Earth and Planetary Astrophysics · Physics 2015-06-23 Tsevi Mazeh , Hagai B. Perets , Amy McQuillan , Eyal S. Goldstein
‹ Prev 1 4 5 6 7 8 10 Next ›