Results 81 to 90 of about 4,942 (197)
Radial Velocity Variations from Starspots [PDF]
International Astronomical Union Colloquium, 1999 AbstractIn this contribution the radial velocity (RV) variations expected for starspots on solar-type stars are examined. The spot-induced RV amplitude is found to vary linearly with spot filling factor and is less than 1 m−1 for spot sizes comparable to large sunspots and as high as 20 m s−1 for spot filling factors of 1%.
openaire +1 more source
MODELING SUNSPOT AND STARSPOT DECAY BY TURBULENT EROSION [PDF]
The Astrophysical Journal, 2015 Astrophysical Journal ...
Litvinenko, Yuri E., Wheatland, M. S.
openaire +2 more sources
Doppler imaging of the young late-type star LO Pegasi (BD +22 4409) in September 2003
, 2008 A Doppler image of the ZAMS late-type rapidly rotating star LO Pegasi, based on spectra acquired between 12 and 15 September 2003, is presented. The Least Square Deconvolution technique is applied to enhance the signal-to-noise ratio of the mean ...
Donati, J. -F. +4 more
core +3 more sources
Molecules as magnetic probes of starspots [PDF]
Astronomy & Astrophysics, 2015 Stellar dynamo processes can be explored by measuring the magnetic field. This is usually obtained using the atomic and molecular Zeeman effect in spectral lines. While the atomic Zeeman effect can only access warmer regions, the use of molecular lines is of advantage for studying cool objects.
Afram, N., Berdyugina, S. V.
openaire +2 more sources
Starspot induced effects in microlensing events with rotating source star
, 2015 We consider the effects induced by the presence of hot and cold spots on the source star in the light curves of simulated microlensing events due to either single or binary lenses taking into account the rotation of the source star and the orbital motion
De Paolis, Francesco +3 more
core +1 more source
The microlensing signatures of starspots
, 2002 Point lens microlensing events with impact parameter close to the source stellar radius allow the observer to study the surface brightness profile of the lensed source. We have examined the effect of photospheric star spots on multicolour microlensing lightcurves and investigated the detectability of such spots in different wavebands as a function of ...
Hendry, M. A. +2 more
openaire +2 more sources
The Astrophysical Journal, 1974 Sizes of starspots on flare stars can be derived from the author's convection-cell hypothesis. The sizes are in fair agreement with those observed on YY Gem, CC Eri, and BY Dra by Bopp and Evans (1973). The hypothesis predicts that periodic brightness variations due to starspots are restricted to stars brighter than a critical absolute visual ...
openaire +1 more source
Further Study of Starspot Activity and Measurement of Differential Rotation for SZ Piscium
The Astrophysical JournalWe present a series of nine Doppler images of the magnetically active K component of the RS CVn-type binary SZ Piscium (SZ Psc), based on high-resolution spectroscopic data collected from 2014 to 2018.
Yue Xiang +4 more
doaj +1 more source
Sunspots, Starspots, and Elemental Abundances
The Astrophysical Journal, 2017 Abstract Element abundances in the solar photosphere, chromosphere, transition region, and corona are key parameters for investigating sources of the solar wind and for estimating radiative losses in the quiet corona and in dynamical events such as solar flares.
G. A. Doschek, H. P. Warren
openaire +1 more source
EPJ Web of Conferences, 2017 Starspots are cooler and darker than the stellar surface. Therefore, the emitted flux of a star changes when spots are visible on its surface. The presence of spots together with the stellar rotation leads to a periodic modulation on the light curve.
Santos Ângela R. G. +4 more
doaj +1 more source