Results 41 to 50 of about 205 (134)
Surface image and activity-corrected orbit of the RSCVn binary HR7275
Astronomy & AstrophysicsContext. Quantifying stellar parameters and magnetic activity for cool stars in double-lined spectroscopic binaries (SB2s) is not straightforward, as both stars contribute to the observed composite spectra and are likely variable.
Adebali Ö. +5 more
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Subduction, Stratosphere, Starspots, and Sushi
Eos, 2017 Highlights from AGU’s joint meeting with the Japan Geophysical Union.
Jenny Lunn +4 more
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Stellar Flares, Superflares, and Coronal Mass Ejections—Entering the Big Data Era
UniverseFlares, sometimes accompanied by coronal mass ejections (CMEs), are the result of sudden changes in the magnetic field of stars with high energy release through magnetic reconnection, which can be observed across a wide range of the electromagnetic ...
Krisztián Vida +8 more
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The Astrophysical Journal, 2023 Stellar rotation is crucial for studying stellar evolution, since it provides information about age, angular momentum transfer, and magnetic fields of stars.
Alexandre Araújo, Adriana Valio
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Modeling Stellar Ca ii H and K Emission Variations: Spot Contribution to the S-index
The Astrophysical Journal Letters, 2023 The S -index is a measure of emission in the Ca ii H and K lines and is a widely used proxy of stellar magnetic activity. It has been assumed until now that the S -index is mainly affected by bright plage regions in the chromosphere.
K. Sowmya +4 more
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Starspots on by DRA-Type Stars [PDF]
Highlights of Astronomy, 1977 The first detection of spots on dwarf M stars was by Kron on YY Geminorum in 1948. Since then phenomena attributable to starspots have been found by numerous authors beginning with Kraft and Krzeminski on the star now known as BY Draconis and on CC Eridani by Evans.
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Multiple short-term cycles in Kepler star KIC 6876668
Astronomy & AstrophysicsContext. Solar and stellar magnetic activity may have similar properties, which can be used to understand the stellar magnetic evolution. Aims. This paper examines the multiple short-term cycles in the total irradiance of the Sun and in the light curve ...
Gurgenashvili E. +5 more
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The Astronomical Journal, 2023 We perform an in-depth analysis of the recently validated TOI-3884 system, an M4-dwarf star with a transiting super-Neptune. Using high-precision light curves obtained with the 3.5 m Apache Point Observatory and radial velocity observations with the ...
Jessica E. Libby-Roberts +27 more
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Starspots, cycles, and magnetic fields [PDF]
Proceedings of the International Astronomical Union, 2010 AbstractI make a perhaps slightly foolhardy attempt to synthesize a semi-coherent scenario relating cycle characteristics, starspots, and the underlying magnetic fields with stellar properties such as mass and rotation. Key to this attempt is to first study single dwarfs; differential rotation plays a surprising role.
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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%.
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