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Related papers: Chromospheric turbulence as a regulator of stellar…

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We study the formation and evolution of a turbulent spectrum of Alfv\'en waves driven by reflection off the solar wind density gradients, starting from the coronal base up to 17 solar radii, well beyond the Alfv\'enic critical point. The…

Solar and Stellar Astrophysics · Physics 2009-07-22 A. Verdini , M. Velli , E. Buchlin

Although the mechanisms responsible for heating the Sun's corona and accelerating the solar wind are still being actively investigated, it is largely accepted that photospheric motions provide the energy source and that the magnetic field…

Solar and Stellar Astrophysics · Physics 2015-06-18 Roberto Lionello , Marco Velli , Cooper Downs , Jon A. Linker , Zoran Mikić , Andrea Verdini

The solar wind is connected to the Sun's atmosphere by flux tubes that are rooted in an ever-changing pattern of positive and negative magnetic polarities on the surface. Observations indicate that the magnetic field is filamentary and…

Solar and Stellar Astrophysics · Physics 2015-06-15 Steven R. Cranmer , Adriaan A. van Ballegooijen , Lauren N. Woolsey

All molecular clouds are observed to be turbulent, but the origin, means of sustenance, and evolution of the turbulence remain debated. One possibility is that stellar feedback injects enough energy into the cloud to drive observed motions…

Astrophysics of Galaxies · Physics 2016-12-28 Ryan D. Boyden , Eric W. Koch , Erik W. Rosolowsky , Stella S. R. Offner

Supersonic turbulence in molecular clouds is a dominant agent that strongly affects the clouds' evolution and star formation activity. Turbulence may be initiated and maintained by a number of processes, acting at a wide range of physical…

Astrophysics of Galaxies · Physics 2014-11-20 C. M. Brunt , M. H. Heyer , M. -M. Mac Low

Turbulence is a phenomenon found throughout space and astrophysical plasmas. It plays an important role in solar coronal heating, acceleration of the solar wind, and heating of the interstellar medium. Turbulence in these regimes is…

Solar and Stellar Astrophysics · Physics 2015-06-16 D. J. Drake , J. W. R. Schroeder , G. G. Howes , C. A. Kletzing , F. Skiff , T. A. Carter , D. W. Auerbach

I develop a detailed empirical model for the chromosphere and wind of 31 Cyg based on a previously published analysis of IUE spectra from the 1993 eclipse and on the thermodynamics of how the wind must be driven. I then use this model to…

Astrophysics · Physics 2009-11-13 Joel A. Eaton

Recent observations have demonstrated that waves which are capable of carrying large amounts of energy are ubiquitous throughout the solar corona. However, the question of how this wave energy is dissipated (on which time and length scales)…

Solar and Stellar Astrophysics · Physics 2014-11-20 Jiajia Liu , Scott W. McIntosh , Ineke De Moortel , James Threlfall , Christian Bethge

Alfv\'{e}nic component of MHD turbulence damps Alfv\'{e}nic waves. The consequences of this effect are important for many processes, from cosmic ray (CR) propagation to launching outflows and winds in galaxies and other magnetized systems.…

Astrophysics of Galaxies · Physics 2022-01-17 Alex Lazarian , Siyao Xu

An evolving turbulent flow such as the solar wind can be meaningfully characterized by its "turbulence age" -- an estimate of the number of nonlinear times that have elapsed during a plasma parcel's propagation from the Sun to a given point…

Solar and Stellar Astrophysics · Physics 2026-03-30 Rohit Chhiber , Yanwen Wang , Arcadi V. Usmanov , William H. Matthaeus

We make use of the Parker Solar Probe (PSP) data to explore the nature of solar wind turbulence focusing on the Alfv\'enic character and power spectra of the fluctuations and their dependence on distance and context (i.e. large scale solar…

The role of turbulence in various astrophysical settings is reviewed. Among the differences to laboratory and atmospheric turbulence we highlight the ubiquitous presence of magnetic fields that are generally produced and maintained by…

Solar and Stellar Astrophysics · Physics 2015-03-13 Axel Brandenburg , Aake Nordlund

We review our recent results of Alfven wave-driven winds. First, we present the result of a self-consistent 1D MHD simulations for solar winds from the photosphere to interplanetary region. Here, we emphasize the importance of the…

Solar and Stellar Astrophysics · Physics 2015-05-18 Takeru K. Suzuki

We revisit the role of longitudinal waves in driving the solar wind. We study how the the $p$-mode-like vertical oscillation on the photosphere affects the properties of solar winds under the framework of Alfv\'en-wave-driven winds. We…

Solar and Stellar Astrophysics · Physics 2022-09-14 Kimihiko Shimizu , Munehito Shoda , Takeru K. Suzuki

Magnetic interactions between close-in planets and their host star can play an important role in the secular orbital evolution of the planets, as well as the rotational evolution of their host. As long as the planet orbits inside the…

Earth and Planetary Astrophysics · Physics 2015-06-22 Antoine Strugarek , Allan Sacha Brun , Sean Patrick Matt , Victor Réville

M dwarf's atmosphere and wind is expected to be highly magnetized. The nonlinear propagation of Alfv\'en wave could play a key role in both heating the stellar atmosphere and driving the stellar wind. Along this Alfv\'en wave scenario, we…

Solar and Stellar Astrophysics · Physics 2021-01-20 Takahito Sakaue , Kazunari Shibata

Alfv\'en waves are responsible for the transfer of magnetic energy in the magnetized plasma. They are involved in heating solar atmosphere and driving solar wind through various nonlinear processes. Since the magnetic field configurations…

Solar and Stellar Astrophysics · Physics 2020-08-04 Takahito Sakaue , Kazunari Shibata

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

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

We study the role the the p-mode-like vertical oscillation on the photosphere in driving solar winds in the framework of Alfven-wave-driven winds. By performing one-dimensional magnetohydrodynamical numerical simulations from the…

Solar and Stellar Astrophysics · Physics 2022-11-10 Kimihiko Shimizu , Munehito Shoda , Takeru K. Suzuki