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Related papers: Deciphering solar turbulence from sunspots records

200 papers

Sunspots are concentrations of magnetic field visible on the solar surface (photosphere). It was considered implausible that solar flares, as resulted from magnetic reconnection in the tenuous corona, would cause a direct perturbation of…

Solar and Stellar Astrophysics · Physics 2017-05-12 Chang Liu , Yan Xu , Wenda Cao , Na Deng , Jeongwoo Lee , Hugh S. Hudson , Dale E. Gary , Jiasheng Wang , Ju Jing , Haimin Wang

Using high resolution Cluster satellite observations, we show that the turbulent solar wind is populated by magnetic discontinuities at different scales, going from proton down to electron scales. The structure of these layers resembles the…

Solar and Stellar Astrophysics · Physics 2016-06-08 A. Greco , S. Perri , S. Servidio , E. Yordanova , P. Veltri

Turbulence is a chaotic flow regime filled by irregular flows. The dissipation of turbulence is a fundamental problem in the realm of physics. Theoretically, dissipation cannot be ultimately achieved without collisions, and so how turbulent…

Space Physics · Physics 2016-01-01 Y. Wang , F. S. Wei , X. S. Feng , X. J. Xu , J. Zhang , T. R. Sun , P. B. Zuo

Vortex-type motions have been measured by tracking bright points in high-resolution observations of the solar photosphere. These small-scale motions are thought to be determinant in the evolution of magnetic footpoints and their interaction…

Solar and Stellar Astrophysics · Physics 2015-05-18 L. Balmaceda , S. Vargas Domínguez , J. Palacios , I. Cabello , V. Domingo

Astrophysical fluids, including interstellar and interplanetary medium, are magnetized and turbulent. Their appearance, evolution, and overall properties are determined by the magnetic turbulence that stirs it. We argue that examining…

Astrophysics · Physics 2009-11-13 A. Lazarian , A. Beresnyak , H. Yan , M. Opher , Y. Liu

We report on the occurrence of small-scale vortices in simulations of the convective solar surface. Using an eigenanalysis of the velocity gradient tensor, we find the subset of high vorticity regions in which the plasma is swirling. The…

Solar and Stellar Astrophysics · Physics 2015-05-30 R. Moll , R. H. Cameron , M. Schüssler

The solar wind is a magnetized and turbulent plasma. Its turbulence is often dominated by Alfv\'enic fluctuations and often deemed as nearly incompressible far away from the Sun, as shown by in-situ measurements near 1AU. However, for solar…

Solar and Stellar Astrophysics · Physics 2022-09-14 Xiangrong Fu , Hui Li , Zhaoming Gan , Senbei Du , John Steinberg

Incompressible Magnetohydrodynamics is often assumed to describe solar wind turbulence. We use extended self similarity to reveal scaling in structure functions of density fluctuations in the solar wind. Obtained scaling is then compared…

Astrophysics · Physics 2009-11-10 Bogdan Hnat , Sandra C. Chapman , George Rowlands

The nature of turbulence at sub-electron scales has remained an open question, central to understanding how electrons are heated in the solar wind. This is primarily because spacecraft measurements have been limited to magnetic field…

Space Physics · Physics 2026-01-21 Shiladittya Mondal , Christopher H. K. Chen , Davide Manzini

We have discovered small whirlpools in the Sun, with a size similar to the terrestrial hurricanes (<~0.5 Mm). The theory of solar convection predicts them, but they had remained elusive so far. The vortex flows are created at the downdrafts…

Astrophysics · Physics 2009-11-13 J. A. Bonet , I. Marquez , J. Sanchez Almeida , I. Cabello , V. Domingo

Hot luminous stars show a variety of phenomena in their photospheres and in their winds which still lack clear physical explanations at this time. Among these phenomena are non-thermal line broadening, line profile variability (LPVs),…

Solar and Stellar Astrophysics · Physics 2012-04-09 Matteo Cantiello , Jonathan Braithwaite , Axel Brandenburg , Fabio Del Sordo , Petri Käpylä , Norbert Langer

Magnetic flux emergence from the convection zone into the photosphere and beyond is a critical component of the behaviour of large-scale solar magnetism. Flux rarely emerges amid field-free areas at the surface, but when it does, the…

Solar and Stellar Astrophysics · Physics 2024-03-04 Prasad Mani , Chris S. Hanson , Siddarth Dhanpal , Shravan Hanasoge , Srijan Bharati Das , Matthias Rempel

Turbulence develops in any stressed flow when the scales of the forcing are much larger than those of the dissipation. In neutral fluids, it consists of chaotic motions in physical space but with a universal energy spectrum in Fourier…

Solar oscillations consist of a rich spectrum of internal acoustic waves and surface gravity waves, stochastically excited by turbulent convection. They have been monitored almost continuously over the last ten years with high-precision…

Astrophysics · Physics 2010-11-26 L. Gizon

Solar prominences are long-lived cool and dense plasma curtains in the hot and rarefied outer solar atmosphere or corona. The physical mechanism responsible for their formation and especially for their internal plasma circulation has been…

Solar and Stellar Astrophysics · Physics 2016-05-25 Chun Xia , Rony Keppens

The solar corona has been revealed in the past decade to be a highly dynamic nonequilibrium plasma environment. Both the loop-filled coronal base and the extended acceleration region of the solar wind appear to be strongly turbulent, but…

Astrophysics · Physics 2008-11-26 Steven R. Cranmer

Observations of solar prominences reveal a complex, dynamic flow field within them. The flow field within quiescent prominences is characterized by long ``threads'' and dark ``bubbles'' that fall and rise (respectively) in a thin sheet. The…

Solar and Stellar Astrophysics · Physics 2012-01-23 Neal Hurlburt , Thomas Berger

We study intermittency as a departure from self-similarity of the solar wind magnetic turbulence and investigate the evolution with the heliocentric distance and latitude. We use data from the Ulysses spacecraft measured during two solar…

Space Physics · Physics 2016-08-24 Anna Wawrzaszek , Marius Echim , Wiesław M. Macek , Roberto Bruno

The degree of linear polarization has recently been found to show wide random variations over the solar disk. These variations are presumably at least partly due to fluctuations in the flux density of turbulent photospheric magnetic fields…

Astrophysics · Physics 2007-05-23 K. Petrovay

The issue of predicting solar flares is one of the most fundamental in physics, addressing issues of plasma physics, high-energy physics, and modelling of complex systems. It also poses societal consequences, with our ever-increasing need…

Solar and Stellar Astrophysics · Physics 2014-11-20 R. T. James McAteer , Peter T. Gallagher , Paul A. Conlon