Results 11 to 20 of about 205 (134)
Torus-stable zone above starspots [PDF]
Monthly Notices of the Royal Astronomical Society, 2021 ABSTRACT Whilst intense solar flares are almost always accompanied by a coronal mass ejection (CME), reports on stellar CMEs are rare, despite the frequent detection of stellar ‘super flares’. The torus instability of magnetic flux ropes is believed to be one of the main driving mechanisms of solar CMEs.
Sun, Xudong +2 more
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The Astronomical Journal, 2016 ABSTRACT By analyzing K2 short-cadence observations, we detect starspots on WASP-85A, the host star of the hot Jupiter WASP-85Ab. The detection of recurring starspot occultation events indicates that the planet’s orbit is aligned with the star’s rotational axis ( λ
T. Močnik +4 more
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ON SUNSPOT AND STARSPOT LIFETIMES [PDF]
The Astrophysical Journal, 2014 We consider the lifetimes of spots on the Sun and other stars from the standpoint of magnetic diffusion. While normal magnetic diffusivity predicts lifetimes of sunspots that are too large by at least two orders of magnitude, turbulent magnetic diffusivity accounts for both the functional form of the solar empirical spot-lifetime relation and for the ...
S. J. Bradshaw, P. Hartigan
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3D Radiative MHD Simulations of Starspots [PDF]
The Astrophysical Journal, 2020 Abstract There are no direct spatially resolved observations of spots on stars other than the Sun, and starspot properties are inferred indirectly through lightcurves and spectropolarimetric data. We present the first self-consistent 3D radiative MHD computations of starspots on G2V, K0V, and M0V stars, which will help us to better ...
Mayukh Panja +2 more
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Under-Developed and Under-Utilized Eclipsing Binary Model Capabilities [PDF]
Journal of Astronomy and Space Sciences, 2012 Existing but largely unused binary star model capabilities are examined. An easily implemented scheme is parameterization of starspot growth and decay that can stimulate work on outer convection zones and their dynamos.
R. E. Wilson
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Light curve analysis of W-UMa type binary systems RZ UMi, OQ UMa, LP UMa [PDF]
Serbian Astronomical JournalThis study presents new, high-quality, optical photometric observations of three W-UMa type contact binaries. The analysis of the corresponding light curves is made using Djurašević's inverse problem method.
Grozdanović M., Đurašević G.
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Joint Modeling of Radial Velocities and Photometry with a Gaussian Process Framework
The Astrophysical Journal, 2023 Developments in the stability of modern spectrographs have led to extremely precise instrumental radial velocity (RV) measurements. For most stars, the detection limit of planetary companions with these instruments is expected to be dominated by ...
Quang H. Tran +3 more
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A New Approach to the Long-Term Activity Behavior of DM UMa
Open Astronomy, 2012 A long-term activity character of DM UMa (K0-1 IV-III), which is one of the most active members of the RS CVn type variables, is examined using the multicolor photometric observations which spread to the time interval between 1980 and 2009. In this work,
Taş G., Evren S.
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Contemporaneous Observations of Hα Luminosities and Photometric Amplitudes for M Dwarfs
The Astronomical Journal, 2023 While many M dwarfs are known to have strong magnetic fields and high levels of magnetic activity, we are still unsure about the properties of their starspots and the origin of their magnetic dynamos.
Aylin García Soto +4 more
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Highlights of Astronomy, 1986 AbstractThe general methodology to detect and study solar-like surface inhomogeneities on stars is presented. The most significant observations and typical results are discussed with particular emphasis on the inferred physical characteristics of starspots and plages and differential rotation, as compared to solar values.
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