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Turbulence in the Sun is suppressed on large scales and confined to equatorial regions.

ABSTRACT: Convection in the Sun's outer envelope generates turbulence and drives differential rotation, meridional circulation, and the global magnetic cycle. We develop a greater understanding of these processes by contrasting observations with simulations of global convection. These comparisons also enhance our comprehension of the physics of distant Sun-like stars. Here, we infer toroidal flow power as a function of wave number, frequency, and depth in the solar interior through helioseismic analyses of space-based observations. The inferred flows grow with spatial wave number and temporal frequency and are confined to low latitudes, supporting the argument that rotation induces systematic differences between the poles and equator. In contrast, the simulations used here show the opposite trends-power diminishing with increasing wave number and frequency while flow amplitudes become weakest at low latitudes. These differences highlight gaps in our understanding of solar convection and point to challenges ahead.

SUBMITTER: Hanasoge SM

PROVIDER: S-EPMC7450475 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Turbulence in the Sun is suppressed on large scales and confined to equatorial regions.

Hanasoge Shravan M SM Hotta Hideyuki H Sreenivasan Katepalli R KR

Science advances 20200722 30

Convection in the Sun's outer envelope generates turbulence and drives differential rotation, meridional circulation, and the global magnetic cycle. We develop a greater understanding of these processes by contrasting observations with simulations of global convection. These comparisons also enhance our comprehension of the physics of distant Sun-like stars. Here, we infer toroidal flow power as a function of wave number, frequency, and depth in the solar interior through helioseismic analyses o ...[more]

PMID: 32923604

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Dataset Information

Turbulence in the Sun is suppressed on large scales and confined to equatorial regions.

Publications

Turbulence in the Sun is suppressed on large scales and confined to equatorial regions.

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