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Related papers: Surface effects in solar-like oscillators

200 papers

Earth's climate can be understood as a dynamical system that changes due to external forcing and internal couplings. Essential climate variables, such as surface air temperature, describe this dynamics. Our current interglacial, the…

Atmospheric and Oceanic Physics · Physics 2022-01-24 Beatrice Ellerhoff , Kira Rehfeld

Convective motions in the deep layers of the solar convection zone are affected by rotation, making the convective heat transport latitude-dependent, but this is not the case in the top layers near the surface. We use the thermal wind…

Solar and Stellar Astrophysics · Physics 2021-02-24 Arnab Rai Choudhuri

We have constructed models for the sun at three stages of its evolution: a zero-age main sequence model, the present sun, and a subgiant model. For each model, the turbulent pressure and turbulent kinetic energy were calculated from 3-d…

Astrophysics · Physics 2007-05-23 P. Demarque , L. H. Li , F. J. Robinson , S. Sofia , Y. -C. Kim , K. L. Chan , D. B. Guenther

Solar p-mode oscillations are excited by the work of stochastic, non-adiabatic, pressure fluctuations on the compressive modes. We evaluate the expression for the radial mode excitation rate derived by Nordlund and Stein (Paper I) using…

Astrophysics · Physics 2009-10-31 R. F. Stein , Å. Nordlund

The total and spectral irradiance varies over short time scales, i.e. from days to months, and longer time scales from years to decades, centuries, and beyond. In this talk we review the current understanding of irradiance changes from days…

Solar and Stellar Astrophysics · Physics 2010-01-29 M. Haberreiter

The description of surface-diffusion controlled dynamics via the phase-field method is less trivial than it appears at first sight. A seemingly straightforward approach from the literature is shown to fail to produce the correct…

Computational Physics · Physics 2017-03-13 Clemens Mueller-Gugenberger , Robert Spatschek , Klaus Kassner

Despite the strong evidence that the peaks in the spectrum of solar oscillations are asymmetric, most determinations of mode frequencies have been based on fits of symmetric Lorentzian profiles to the Fourier or power spectra of oscillation…

Frequency separations used to infer global properties of stars through asteroseismology can change depending on the strength and at what epoch of the stellar cycle the p-mode frequencies are measured. In the Sun these variations have been…

Solar and Stellar Astrophysics · Physics 2015-05-20 O. L. Creevey , D. Salabert , R. A. Garcia

The simple 3-D radiative transfer model in the atmosphere of the Earth is built for numerical comparison of direct solar radiation and limb scattering background at the definite layer during the deep twilight period at the middle and upper…

Atmospheric and Oceanic Physics · Physics 2025-09-05 Oleg S. Ugolnikov

The so-called solar cycle is generally characterized by the quasi-periodic oscillatory evolution of the photospheric spots number. This quasi-periodic pattern has always been an intriguing question. Several physical models were proposed to…

Solar and Stellar Astrophysics · Physics 2015-05-14 Alexis Klutsch , Rubens Freire Ferrero

Successful inference from asteroseismology relies on at least two things: that the oscillations in the stars have amplitudes large enough to be clearly observable; and that the oscillations themselves be stable enough to enable precise…

Solar and Stellar Astrophysics · Physics 2015-05-13 W. J. Chaplin , G. Houdek , C. Karoff , Y. Elsworth , R. New

We describe a global parametric model for the observed power spectra of solar oscillations of intermediate and low degree. A physically motivated parameterization is used as a substitute for a direct description of mode excitation and…

Solar and Stellar Astrophysics · Physics 2015-06-17 Sergei V. Vorontsov , Stuart M. Jefferies

We explore the sensitivity of the frequencies of low-degree solar p-modes to near-surface magnetic flux on different spatial scales and strengths, specifically to active regions with strong magnetic fields and ephemeral regions with weak…

We investigate the effect of localized opacity modifications on the sound-speed profile of solar models. The sound-speed difference between the Sun and a solar model is used to deduce the opacity correction that would be required to bring…

Astrophysics · Physics 2008-02-03 S. C. Tripathy , Sarbani Basu , J. Christensen-Dalsgaard

We present a brief overview of the main effects by which a star will have an impact (positive or negative) on the surface habitability of planets in orbit around it. Specifically, we review how spectral, spatial and temporal variations in…

Earth and Planetary Astrophysics · Physics 2021-04-14 Martin Turbet , Franck Selsis

The status of numerical hydrodynamical models for Planetary Nebulae is reviewed. Since all of the numerical work is based on the interacting winds model, we start with a description of this model and give an overview of the early analytical…

Astrophysics · Physics 2007-05-23 Garrelt Mellema , Adam Frank

We investigate the effects of atmospheric dispersion on observations of the Sun at the ever-higher spatial resolutions afforded by increased apertures and improved techniques. The problems induced by atmospheric refraction are particularly…

Astrophysics · Physics 2008-11-26 Kevin P. Reardon

Wetting phenomena plays an interesting role in the technological development of materials. Recently, much attention has been directed to the study of magnetic solid films. To understand, theoretically, the effect of surface on wetting and…

Materials Science · Physics 2007-05-23 H. Ez-Zahraouy , A. Benyoussef , L. Bahmad

Radiative hydrodynamic simulations of solar and stellar surface convection have become an important tool for exploring the structure and gas dynamics in the envelopes and atmospheres of late-type stars and for improving our understanding of…

Solar and Stellar Astrophysics · Physics 2015-06-03 B. Beeck , R. Collet , M. Steffen , M. Asplund , R. H. Cameron , B. Freytag , W. Hayek , H. -G. Ludwig , M. Schüssler

Large ground- and space-based telescopes will be able to observe Earth-like planets in the near future. We explore how different planetary surfaces can strongly influence the climate, atmospheric composition, and remotely detectable spectra…

Earth and Planetary Astrophysics · Physics 2020-05-20 Jack Madden , Lisa Kaltenegger