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Related papers: Imaging the Sun's near-surface flows using mode-co…

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Detailed knowledge of surface dynamics is one of the key points in understanding magnetic solar activity. The motions of the solar surface, to which we have direct access via the observations, tell us about the interaction between the…

Solar and Stellar Astrophysics · Physics 2023-03-15 T. Roudier , J. Ballot , J. M. Malherbe , M. Chane-Yook

Results of forward modelling of acoustic wave propagation in a realistic solar sub-photosphere with two cases of steady horizontal flows are presented and analysed by the means of local helioseismology. The simulations are based on fully…

Astrophysics · Physics 2009-11-13 S. Shelyag , R. Erdelyi , M. J. Thompson

Expansions in the oscillation modes of tidally perturbed bodies provide a useful framework for representing tidally induced flows. However, recent work has demonstrated that such expansions produce inaccurate predictions for secular orbital…

Solar and Stellar Astrophysics · Physics 2023-10-16 Janosz W. Dewberry , Samantha C. Wu

Fluctuations in the Sun's photospheric magnetic field are the primary source of the turbulence that can heat and accelerate the solar atmosphere, and thus play an important role in the production and evolution of the solar wind that…

Solar and Stellar Astrophysics · Physics 2025-11-26 Rohit Chhiber , Raphael Attie , William H. Matthaeus , Sohom Roy , Barbara J. Thompson

Solar "magnetic tornadoes" are produced by rotating magnetic field structures that extend from the upper convection zone and the photosphere to the corona of the Sun. Recent studies show that such rotating features are an integral part of…

Solar and Stellar Astrophysics · Physics 2017-05-24 Yoshiaki Kato , Sven Wedemeyer

Context: Giant-cell convection is believed to be an important component of solar dynamics. For example, it is expected to play a crucial role in maintaining the Sun's differential rotation. Aims: We re-examine early reports of giant…

Solar and Stellar Astrophysics · Physics 2021-01-04 Chris S. Hanson , Thomas L. Duvall , Aaron C. Birch , Laurent Gizon , Katepalli R. Sreenivasan

Studies of solar and stellar convection often employ simple polytropic setups using the diffusion approximation instead of solving the proper radiative transfer equation. This allows one to control separately the polytropic index of the…

Solar and Stellar Astrophysics · Physics 2014-11-14 Atefeh Barekat , Axel Brandenburg

Downflows on the solar surface are suspected to play a major role in the dynamics of the convection zone. We investigate the existence of the long-lasting downflows whose effects influence the interior of the Sun and the outer layers. We…

Solar and Stellar Astrophysics · Physics 2021-03-05 T. Roudier , M. Švanda , J. M. Malherbe , J. Ballot , D. Korda , Z. Frank

We perform helioseismic holography on realistic solar convection simulations and compare the observed travel-time perturbations with the expected travel times from the horizontal flows in the simulations computed from forward models under…

Astrophysics · Physics 2016-03-28 D. C. Braun , A. C. Birch , D. Benson , R. F. Stein , Å. Nordlund

Model simulations of solar irradiance reaching the Earth's surface during a solar eclipse constitute a useful tool for studying the impact of this phenomenon on the radiance propagation through the atmosphere. A simple approach to extend…

Atmospheric and Oceanic Physics · Physics 2011-10-11 Boyan Petkov , Claudio Tomasi , Vito Vitale , Christian Lanconelli , Mauro Mazzola

Doppler Imaging (DI) is a well-established technique to map a physical field at a stellar surface from a time series of high-resolution spectra. In this proof-of-concept study, we aim to show that traditional DI algorithms, originally…

North-south (N-S) asymmetry of solar activity is a known statistical phenomenon but its significance is difficult to prove or theoretically explain. Here we consider each solar hemisphere as a separate dynamical system connected with the…

Solar and Stellar Astrophysics · Physics 2017-04-06 D. M. Volobuev , N. G. Makarenko

The study of solar oscillations (helioseismology) has been a very successful method of researching the Sun. Helioseismology teaches us about the structure and mean properties of the Sun. Together with mid-resolution data, the local…

Solar and Stellar Astrophysics · Physics 2021-10-20 David Korda , Michal Švanda , Thierry Roudier

We perform a two-dimensional inversion of f-mode travel times to determine near-surface solar flows. The inversion is based on optimally localized averaging of travel times. We use finite-wavelength travel-time sensitivity functions and a…

Astrophysics · Physics 2009-11-13 J. Jackiewicz , L. Gizon , A. C. Birch , M. J. Thompson

Optical observations of solar corona provide key information on its magnetic geometry. The large-scale open field of the corona plays an important role in shaping the ambient solar wind and constraining the propagation dynamics of the…

Solar and Stellar Astrophysics · Physics 2025-06-19 Vadim M. Uritsky , Christopher E. Rura , Cooper Downs , Shaela I. Jones , Charles Nickolos Arge , Nathalia Alzate

The strongly interacting system created in ultrarelativistic nuclear collisions behaves almost as an ideal fluid with rich patterns of the velocity field exhibiting strong vortical structure. Vorticity of the fluid, via spin-orbit coupling,…

Nuclear Experiment · Physics 2024-10-30 Takafumi Niida , Sergei A. Voloshin

The principal component analysis of flow correlations in heavy-ion collisions is studied. The correlation matrix of harmonic flow is generalized to correlations involving several different flow vectors. The method can be applied to study…

Nuclear Theory · Physics 2018-03-14 Piotr Bozek

We present a new methodology -- the Keplerian Optical Dynamics Analysis (KODA) -- for analyzing the dynamics of dense, cool material in the solar corona. The technique involves adaptive spatiotemporal tracking of propagating intensity…

Solar and Stellar Astrophysics · Physics 2022-08-24 V. M. Uritsky , B. J. Thompson , C. R. DeVore

The observed solar activity is believed to be driven by the dissipation of nonpotential magnetic energy injected into the corona by dynamic processes in the photosphere. The enormous range of scales involved in the interaction makes it…

Solar and Stellar Astrophysics · Physics 2015-06-12 Vadim M. Uritsky , Joseph M. Davila , Leon Ofman , Aaron J. Coyner

This paper is devoted to the robust approximation with a variational phase field approach of multiphase mean curvature flows with possibly highly contrasted mobilities. The case of harmonically additive mobilities has been addressed…

Numerical Analysis · Mathematics 2022-09-20 Eric Bonnetier , Elie Bretin , Simon Masnou