Results 11 to 20 of about 130,683 (338)
The Stellar Activity - Rotation Relationship [PDF]
Astronomische Nachrichten, 2012 Using a new catalog of 824 solar and late-type stars with X-ray luminosities and rotation periods we have studied the relationship between rotation and stellar activity. From an unbiased subset of this sample the power law slope of the unsaturated regime,
Drake, Jeremy J. +3 more
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Highlights of Astronomy, 1986 AbstractThe main features of solar and stellar activity cycles are summarized, followed by a discussion of some outstanding observational problems for the future.
Dainis Dravins
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Stellar Chromospheric Activity [PDF]
Living Reviews in Solar Physics, 2008 The Sun, stars similar to it, and many rather dissimilar to it, have chromospheres, regions classically viewed as lying above the brilliant photosphere and characterized by a positive temperature gradient and a marked departure from radiative equilibrium.
Hall Jeffrey C.
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Asteroseismic stellar activity relations [PDF]
Astronomy & Astrophysics, 2014 In asteroseismology an important diagnostic of the evolutionary status of a star is the small frequency separation which is sensitive to the gradient of the mean molecular weight in the stellar interior.
Bonanno, A., Corsaro, E., Karoff, C.
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Reconstructing Intrinsic Stellar Noise with Stellar Atmospheric Parameters and Chromospheric Activity [PDF]
The Astrophysical Journal Supplement SeriesAccurately characterizing the intrinsic stellar photometric noise induced by stellar astrophysics, such as stellar activity, granulation, and oscillations, is of crucial importance for detecting transiting exoplanets.
Jinghua Zhang +11 more
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Space Science Reviews, 2023 AbstractThe magnetic field of the Sun is generated by internal dynamo process with a cyclic period of 11 years or a 22 year magnetic cycle. The signatures of the Sun’s magnetic cycle are observed in the different layers of its atmosphere and in its internal layers.
Jeffers, Sandra V. +2 more
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Symposium - International Astronomical Union, 1986 We have been monitoring the CaII H and K emission in late-type giant stars using the Mt Wilson 60-inch telescope. It is a continuation of work that Olin Wilson began almost 20 years ago. As a result not only have starspot cycles been detected (equivalent to the solar sunspot cycle), but rotation periods have now been measured.
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, 2009 The solar activity cycle is a manifestation of the hydromagnetic dynamo working inside our star. The detection of activity cycles in solar-like stars and the study of their properties allow us to put the solar dynamo in perspective, investigating how ...
A. F. Lanza +38 more
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Solar and Stellar Flares: Frequency, Active Regions, and Stellar Dynamo
The Astrophysical Journal, 2022 Abstract We demonstrate that for weak flares the dependence of their frequency occurrence on spottedness can be rather weak. The fact is that such flares can occur in both small and large active regions. At the same time, powerful large flares of classes M and X occur much more often in large active regions. In energy estimates, the mean
M. M. Katsova +3 more
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Multiple views of magnetism in cool stars [PDF]
, 2012 Magnetic fields are regarded as a crucial element for our understanding of stellar physics. They can be studied with a variety of methods which provide complementary - and sometimes contradictory - information about the structure, strength and dynamics ...
Arzoumanian +24 more
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