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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

Recently Gizon, Duvall and Schou (2002) suggested that supergranulation has a wave-like component. In this paper I show that the same phenomenon can be observed using surface Doppler shift data, thereby confirming their observations. I am…

Astrophysics · Physics 2007-05-23 J. Schou

The motions of the plasma and structures in and below the solar photosphere is not well understood. The results obtained using various methods cannot be in general considered as consistent, especially in details. In this contribution we…

Astrophysics · Physics 2008-09-30 M. Svanda , M. Klvana , M. Sobotka

We investigate how rotationally-constrained, deep convection might give rise to supergranulation, the largest distinct spatial scale of convection observed in the solar photosphere. While supergranulation is only weakly influenced by…

Solar and Stellar Astrophysics · Physics 2016-10-19 Nicholas A. Featherstone , Bradley W. Hindman

Recently, Duvall and Hanasoge ({\it Solar Phys.} {\bf 287}, 71-83, 2013) found that large distance $[\Delta]$ separation travel-time differences from a center to an annulus $[\delta t_{\rm{oi}}]$ implied a model of the average supergranular…

Solar and Stellar Astrophysics · Physics 2015-06-19 T. L. Duvall , S. M. Hanasoge , S. Chakraborty

Results of realistic simulations of solar surface convection on the scale of supergranules (96 Mm wide by 20 Mm deep) are presented. The simulations cover only 10% of the geometric depth of the solar convection zone, but half its pressure…

Astrophysics · Physics 2008-11-05 R. F. Stein , A. Nordlund , D. Georgobiani , D. Benson , W. Schaffenberger

Recent analysis revealed that supergranules (convection cells seen at the Sun's surface) are advected by the zonal flows at depths equal to the widths of the cells themselves. Here we probe the structure of the meridional circulation by…

Solar and Stellar Astrophysics · Physics 2015-06-11 David H. Hathaway

We model the solar horizontal velocity power spectrum at scales larger than granulation using a two-component approximation to the mass continuity equation. The model takes four times the density scale height as the integral (driving) scale…

Solar and Stellar Astrophysics · Physics 2015-06-22 J. W. Lord , R. H. Cameron , M. P. Rast , M. Rempel , T. Roudier

Photospheric vortex flows are thought to play a key role in the evolution of magnetic fields. Recent studies show that these swirling motions are ubiquitous in the solar surface convection and occur in a wide range of temporal and spatial…

Solar and Stellar Astrophysics · Physics 2018-03-07 Iker S. Requerey , Basilio Ruiz Cobo , Milan Gošić , Luis R. Bellot Rubio

Spectral analysis of the spatial structure of solar subphotospheric convection is carried out for subsurface flow maps constructed using the time--distance helioseismological technique. The source data are obtained from the Helioseismic and…

Solar and Stellar Astrophysics · Physics 2022-09-27 Alexander V. Getling , Alexander G. Kosovichev

We show that the motions of supergranules are consistent with a model in which they are simply advected by the axisymmetric flows in the Sun's surface shear layer. We produce a 10-day series of simulated Doppler images at a 15-minute…

Solar and Stellar Astrophysics · Physics 2015-05-19 David H. Hathaway , Peter E. Williams , Kevin Dela Rosa , Manfred Cuntz

Heat is transported through the outermost 30% of the Sun's interior by overturning convective motions. These motions are evident at the Sun's surface in the form of two characteristic cellular structures - granules and supergranules (~1000…

Solar and Stellar Astrophysics · Physics 2014-01-06 David H. Hathaway , Lisa Upton , Owen Colegrove

We present here numerical simulations of surface solar convection which cover a box of 30$\times30\times$3.2 Mm$^3$ with a resolution of 315$\times315\times$82, which is used to investigate the dynamics of scales larger than granulation. No…

Astrophysics · Physics 2010-11-11 M. Rieutord , H. -G. Ludwig , T. Roudier , A. Nordlund , R. Stein

The consistency of time--distance inversions for horizontal components of the plasma flow on supergranular scales in the upper solar convection zone is checked by comparing the results derived using two k--\omega filtering procedures --…

Solar and Stellar Astrophysics · Physics 2015-06-16 Michal Svanda

Magnetoconvection at the solar surface governs the dynamics in the upper solar atmosphere and sustains the heliosphere. Properties of this fundamental process are poorly described near the solar poles. Here we report the first…

Emerging active regions are associated with convective flows on the spatial scale and lifetimes of supergranules. To understand how these flows are involved in the formation of active regions, we aim to identify where active regions emerge…

Solar and Stellar Astrophysics · Physics 2024-07-17 Hannah Schunker , William Roland-Batty , Aaron C. Birch , Douglas C. Braun , Robert H. Cameron , L. Gizon

Turbulent convection processes in nature are often found to be organized in a hierarchy of plume structures and flow patterns. The gradual aggregation of convection cells or granules to a supergranule which eventually fills the whole…

Fluid Dynamics · Physics 2021-03-16 Philipp P. Vieweg , Janet D. Scheel , Jörg Schumacher

Solar supergranulation remains a mystery in spite of decades of intensive studies. Most of the papers about supergranulation deal with its surface properties. Local helioseismology provides an opportunity to look below the surface and see…

Solar and Stellar Astrophysics · Physics 2015-05-19 Radek Zlebcik , Michal Svanda , Mirek Klvana

We show that contrary to what is expected from 1D stationary model atmospheres, 3D hydrodynamical modeling predicts a considerable influence of convection on the spectral properties of late-type giants. This is due to the fact that…

Astrophysics · Physics 2009-11-11 A. Kucinskas , H. -G. Ludwig , P. H. Hauschildt

We examine the role of small-scale granulation in helping to drive supergranulation and even larger scales of convection. The granulation is modeled as localized cooling events introduced at the upper boundary of a 3-D simulation of…

Solar and Stellar Astrophysics · Physics 2012-01-24 Neal Hurlburt , Marc DeRosa , Kyle Augustson , Juri Toomre