Results 11 to 20 of about 1,037 (263)

Scaling Relations for Solar-Like Oscillations: A Review

Frontiers in Astronomy and Space Sciences, 2020
The scaling relations for solar-like oscillations provide a translation of the features of the stochastic low-degree modes of oscillation in the Sun to predict the features of solar-like oscillations in other stars with convective outer layers.
Saskia Hekker, Saskia Hekker
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An Oscillator Model for Stellar Variability [PDF]

International Astronomical Union Colloquium, 1993
AbstractThe dependence of coupling constants in a coupled oscillator model is examined with simplified methods. The Lyapunov exponents are preliminary introduced for the model. The behaviors of oscillator model are examined in a parameter plane. So-called the Arnold’s tongues for phase-locking states are observed in fractal patterns.
T. Nakahara, Y. Tanaka
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A MULTI-PERIOD OSCILLATION IN A STELLAR SUPERFLARE [PDF]

The Astrophysical Journal, 2015
Flares that are orders of magnitude larger than the most energetic solar flares are routinely observed on Sun-like stars, raising the question of whether the same physical processes are responsible for both solar and stellar flares. In this letter we present a white-light stellar superflare on the star KIC9655129, observed by NASA's Kepler mission ...
C. E. Pugh, V. M. Nakariakov, A.-M. Broomhall   +2 more
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Asteroseismology and Spectropolarimetry of the Exoplanet Host Star λ Serpentis

The Astronomical Journal, 2023
The bright star λ Ser hosts a hot Neptune with a minimum mass of 13.6 M _⊕ and a 15.5 day orbit. It also appears to be a solar analog, with a mean rotation period of 25.8 days and surface differential rotation very similar to the Sun.
Travis S. Metcalfe, Derek Buzasi, Daniel Huber, Marc H. Pinsonneault, Jennifer L. van Saders, Thomas R. Ayres, Sarbani Basu, Jeremy J. Drake, Ricky Egeland, Oleg Kochukhov, Pascal Petit, Steven H. Saar, Victor See, Keivan G. Stassun, Yaguang Li, Timothy R. Bedding, Sylvain N. Breton, Adam J. Finley, Rafael A. García, Hans Kjeldsen, Martin B. Nielsen, J. M. Joel Ong, Jakob L. Rørsted, Amalie Stokholm, Mark L. Winther, Catherine A. Clark, Diego Godoy-Rivera, Ilya V. Ilyin, Klaus G. Strassmeier, Sandra V. Jeffers, Stephen C. Marsden, Aline A. Vidotto, Sallie Baliunas, Willie Soon   +33 more
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Oscillations in stellar superflares [PDF]

Monthly Notices of the Royal Astronomical Society, 2015
Two different mechanisms may act to induce quasi-periodic pulsations (QPP) in whole-disk observations of stellar flares. One mechanism may be magneto-hydromagnetic (MHD) forces and other processes acting on flare loops as seen in the Sun. The other mechanism may be forced local acoustic oscillations due to the high-energy particle impulse generated by ...
Balona, L.A., Broomhall, A-M., Kosovichev, A., Nakariakov, V.M., Pugh, C.E., Van Doorsselaere, Tom   +5 more
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Semi-analytical Expression of G-mode Period Spacing: The Case of Brunt–Väisälä Frequency with Not a Jump but a Ramp

The Astrophysical Journal, 2023
To decipher complex patterns of gravity-mode period spacings observed for intermediate-mass main-sequence stars is an important step toward a better understanding of the structure and dynamics in the deep radiative region of the stars.
Yoshiki Hatta
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Interaction Between Convection and Pulsation

Living Reviews in Solar Physics, 2015
This article reviews our current understanding of modelling convection dynamics in stars. Several semi-analytical time-dependent convection models have been proposed for pulsating one-dimensional stellar structures with different formulations for how the
Günter Houdek, Marc-Antoine Dupret
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High-eccentricity Migration with Disk-induced Spin–Orbit Misalignment: A Preference for Perpendicular Hot Jupiters

The Astrophysical Journal Letters, 2023
High-eccentricity migration is a likely formation mechanism for many observed hot Jupiters, particularly those with a large misalignment between the stellar spin axis and orbital angular momentum axis of the planet.
Michelle Vick, Yubo Su, Dong Lai
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An essay on stellar oscillations and evolution [PDF]

Solar Physics, 1983
AbstractIt is cautioned that solar models adjusted in such a way as to achieve a match between theoretical solar oscillation characteristics and observed ones may produce neutrino fluxes inconsistent with the observations and that this is likely to be explicable as a deficiency in modeling that portion of the envelope which is most strongly affected by
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Seismological insights into solar and stellar magnetic activity cycles

EPJ Web of Conferences, 2017
The Sun’s magnetic activity cycle varies primarily on a time scale of approximately 11yrs from minimum to maximum and back again. It is well-known that the properties of the Sun’s acoustic oscillations are affected by the near-surface internal magnetic ...
Broomhall Anne-Marie
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