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Related papers: Combined helioseismic inversions for 3D vector flo…

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Our Sun, primarily composed of ionized hydrogen and helium, has a surface temperature of 5777~K and a radius $R_\odot \approx 696,000$ km. In the outer $R_\odot/3$, energy transport is accomplished primarily by convection. Using typical…

Solar and Stellar Astrophysics · Physics 2016-01-20 Shravan Hanasoge , Laurent Gizon , Katepalli R. Sreenivasan

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

White-light images from Heliospheric Imager-1 (HI1) onboard the Solar Terrestrial Relations Observatory (STEREO) provide 2-dimensional (2D) global views of solar wind transients traveling in the inner heliosphere from two perspectives. How…

Solar and Stellar Astrophysics · Physics 2020-08-05 Xiaolei Li , Yuming Wang , Rui Liu , Chenglong Shen , Quanhao Zhang , Shaoyu Lyu , Bin Zhuang , Fang Shen , Jiajia Liu , Yutian Chi

We present a high-resolution, highly stratified numerical simulation of rotating thermal convection in a spherical shell. Our aim is to study in detail the processes that can maintain a near surface shear layer (NSSL) as inferred from…

Solar and Stellar Astrophysics · Physics 2015-06-23 H. Hotta , M. Rempel , T. Yokoyama

The results of determinations of the azimuthal and meridional velocities by time-distance helioseismology from Helioseismic and Magnetic Imager (HMI) onboard Solar Dynamics Observatory (SDO) from May 2010 to September 2020 at latitudes from…

Solar and Stellar Astrophysics · Physics 2021-02-26 Alexander V. Getling , Alexander G. Kosovichev , Junwei Zhao

The Solar Orbiter mission, with an orbit outside the Sun Earth line and leaving the ecliptic plane, opens up opportunities for the combined analysis of measurements obtained by solar imagers and spectrometers. For the first time, different…

Solar and Stellar Astrophysics · Physics 2021-11-24 O. Podladchikova , L. Harra , K. Barczynski , C. H. Mandrini , F. Auchere , D. Berghmans , E. Buchlin , L. Dolla , M. Mierla , S. Parenti , L. Rodriguez

Full-disk observations from missions such as the SDO and SOHO have enabled comprehensive studies of solar oscillations and dynamics. Interpreting helioseismic and photospheric data is complicated by systematic center-to-limb variations. To…

Solar and Stellar Astrophysics · Physics 2026-04-06 Irina N. Kitiashvili

This work proposes a self-navigated variable density spiral(VDS) based manifold regularization scheme to prospectively improve dynamic speech MRI at 3T. Short readout 1.3ms spirals were used to minimize off-resonance. A custom 16-channel…

Image and Video Processing · Electrical Eng. & Systems 2023-05-03 Rushdi Zahid Rusho , Abdul Haseeb Ahmed , Stanley Kruger , Wahidul Alam , David Meyer , David Howard , Brad Story , Mathews Jacob , Sajan Goud Lingala

We discuss current advances in forward and inverse modeling for local helioseismology. We report theoretical uniqueness results, in particular the Novikov-Agaltsov reconstruction algorithm, which is relevant to solving the non-linear…

Solar and Stellar Astrophysics · Physics 2017-07-28 Laurent Gizon , Damien Fournier , Thorsten Hohage

Recent solar photospheric abundance analyses have led to a significant reduction of the metal abundances compared to the previous determinations. The solar models computed with standard opacities and diffusion processes using these new…

Astrophysics · Physics 2015-06-24 M. Castro , S. Vauclair , O. Richard

We present an attempt to reconcile the solar tachocline glitch, a thin layer immediately beneath the convection zone in which the seismically inferred sound speed in the Sun exceeds corresponding values in standard solar models, with a…

Solar and Stellar Astrophysics · Physics 2018-04-04 J. Christensen-Dalsgaard , D. O. Gough , E. Knudstrup

The 'vertical modes and horizontal rays' method, commonly applied for simulating acoustic wave propagation in shallow water is advanced in this research. Our approach to this method involves the use of the so-called space-time rays, which…

Mathematical Physics · Physics 2025-01-08 Aleksandr Kaplun , Boris Katsnelson

Solar wind conditions are predominantly predicted via three-dimensional numerical magnetohydrodynamic (MHD) models. Despite their ability to produce highly accurate predictions, MHD models require computationally intensive high-dimensional…

Computational Physics · Physics 2022-11-30 Opal Issan , Boris Kramer

Schlieren flow visualizations of transverse oscillations of jets submitted to an acoustic perturbation are analyzed in this paper. The aim is to estimate the shape and the position of the median line of the jet. Two methods for image…

Classical Physics · Physics 2008-11-04 Patricio De La Cuadra , Christophe Vergez , Benoit Fabre

Helioseismic inferences of large-scale flows in the solar interior necessitate accounting for the curvature of the Sun, both in interpreting systematic trends introduced in measurements as well as the sensitivity kernel that relates…

Solar and Stellar Astrophysics · Physics 2020-12-23 Jishnu Bhattacharya

We calculate numerically the normal modes of vibrations in 3D jammed packings of soft spheres as a function of the packing fraction and obtain the energy diffusivity, a spectral measure of transport that controls sound propagation and…

Disordered Systems and Neural Networks · Physics 2013-05-29 Vincenzo Vitelli , Ning Xu , Matthieu Wyart , Andrea J. Liu , Sidney R. Nagel

We analyze spectral properties of solar convection in the range of depths from 0 to 19~Mm using subsurface flow maps obtained by the time-distance heiioseismology analysis of solar-oscillation data from the Helioseismic and Magnetic Imager…

Solar and Stellar Astrophysics · Physics 2022-03-01 Alexander V. Getling , Alexander G. Kosovichev

Observations of the Sun in the visible spectral range belong to standard measurements obtained by instruments both on the ground and in the space. Nowadays, both nearly continuous full-disc observations with medium resolution and dedicated…

Solar and Stellar Astrophysics · Physics 2020-06-30 Michal Švanda , Jan Jurčák , David Korda , Jana Kašparová

A major goal of helioseismology is the three-dimensional reconstruction of the three velocity components of convective flows in the solar interior from sets of wave travel-time measurements. For small amplitude flows, the forward problem is…

Numerical Analysis · Mathematics 2017-03-28 D. Fournier , L. Gizon , M. Holzke , T. Hohage

During the last 50 years we have been witness of an extraordinary revolution in the knowledge and understanding of our star thanks to the development of Helioseismology, the study of solar oscillations. Similar to what happens on the Earth…

Solar and Stellar Astrophysics · Physics 2017-06-08 M. P. Di Mauro