相关论文: Detection of differential rotation in psi Cap with…
It is known that stellar differential rotation can be detected by analyzing the Fourier transform of spectral line profiles, since the ratio of the 1st- and 2nd-zero frequencies is a useful indicator. This approach essentially relies on the…
We obtained high quality spectra of 135 stars of spectral types F and later and derived ``overall'' broadening functions in selected wavelength regions utilizing a Least Squares Deconvolution (LSD) procedure. Precision values of the…
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…
While the effect of rotation on spectral lines is complicated in rapidly-rotating stars because of the appreciable gravity-darkening effect differing from line to line, it is possible to make use of this line-dependent complexity to…
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…
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…
We propose a method for measuring the projected rotational velocity $v sin i$ with high-precision even in spectra with blended lines. Though not automatic, our method is designed to be applied systematically to large numbers of objects…
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…
With an aim of getting information on the equatorial rotation velocity (v_e) of Sirius A separated from the inclination effect (sin i), a detailed profile analysis based on the Fourier transform technique was carried out for a large number…
The Fourier Transform method is a popular tool to derive the rotational velocities of stars from their spectral line profiles. However, its domain of validity does not include line-profile variables with time-dependent profiles. We…
Gyrochronology and recent theoretical findings are used to reduce the number of input parameters of differential rotation models. This eventually leads to a theoretical prediction for the surface differential rotation as a function of only…
The solar photosphere, chromosphere and corona are known to rotate differentially as a function of latitude. To date, it is unclear if the solar transition region also rotates differentially. In this paper, we investigate differential…
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…
Stellar rotation influences our understanding of stellar structure and evolution, binary systems, clusters etc. and therefore the benefits of a large and highly accurate database on stellar rotation, obtained by GAIA, will be manifold. To…
We use Doppler imaging techniques to determine the dependence of starspot rotation rates on latitude in an homogeneous sample of young, rapidly-rotating solar analogues. A solar-like differential rotation law is used, where the rotation…
The ESA Herschel Spectral and Photometric Imaging Receiver (SPIRE) Fourier Transform Spectrometer (FTS) Spectral Feature Finder (FF) project is an automated spectral feature fitting routine developed within the SPIRE instrument team to…
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…
V889 Herculis is one of the brightest single early-G type stars, a young Sun, that is rotating fast enough (P_rot =1.337 days) for mapping its surface by Doppler Imaging. The 10 FOCES spectra collected between 13-16 Aug 2006 at Calar Alto…
We used the optical and near-infrared imagers located on the Liverpool, the IAC80, and the William Herschel telescopes to monitor 18 M7$-$L9.5 dwarfs with the objective of measuring their rotation periods. We achieved accuracies typically…
A new version of a numerical model of stellar differential rotation based on mean-field hydrodynamics is presented and tested by computing the differential rotation of the Sun. The model is then applied to four individual stars including…