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Related papers: Alfven Waves in the Lower Solar Atmosphere

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Probing the solar corona is crucial to study the coronal heating and solar wind acceleration. However, the transient and inhomogeneous solar wind flows carry large-amplitude inherent Alfven waves and turbulence, which make detection more…

High-frequency wave phenomena present a great deal of interest as one of the possible candidates to contribute to the energy input required to heat the corona as a part of the AC heating theory. However, the resolution of imaging…

Solar and Stellar Astrophysics · Physics 2023-04-05 Elena Petrova , Norbert Magyar , Tom Van Doorsselaere , David Berghmans

Magnetic fields are key ingredients for heating the solar corona to temperatures of several million Kelvin. A particularly important region with respect to this is the so-called magnetic canopy below the corona, where sound and Alfv\'en…

Solar and Stellar Astrophysics · Physics 2023-01-23 Th. Gundrum , J. Forbriger , Th. Herrmannsdörfer , G. Mamatsashvili , S. Schnauck , F. Stefani , J. Wosnitza

We present observations of persistent oscillations of some bright features in the upper-chromosphere/transition-region above sunspots taken by IRIS SJ 1400 {\AA} and upward propagating quasi-periodic disturbances along coronal loops rooted…

Solar and Stellar Astrophysics · Physics 2018-03-21 Zhenyong Hou , Zhenghua Huang , Lidong Xia , Bo Li , Hui Fu

To study motions and oscillations in the solar chromosphere and at the transition region (TR) level we analyze some extreme Doppler shifts observed off-limb with the Interface Region Imaging Spectrograph (IRIS). Raster scans and slit-jaw…

Solar and Stellar Astrophysics · Physics 2019-09-25 E. Tavabi , S. Koutchmy

A simple model of a periodic ensemble of closely packed flux tubes sitting atop a vertically stratified layer reveals that an incident fast wave from below preferentially converts almost immediately to Alfv\'en waves in the flux tubes, with…

Solar and Stellar Astrophysics · Physics 2017-01-18 Paul S. Cally

The analysis of energy balance of coronal holes gives that to accelerate the fast solar wind streams the energy flux of the order of 800 erg/cm$^2$ s is needed. Axford and McKenzie suggested that the energy source, necessary to accelerate…

Plasma Physics · Physics 2007-05-23 Andrei Sadovski

Nonlinear coupling between 3-minute oscillations and Alfven waves in the solar lower atmosphere is studied. 3-minute oscillations are considered as acoustic waves trapped in a chromospheric cavity and oscillating along transversally…

Astrophysics · Physics 2015-06-24 D. Kuridze , T. V. Zaqarashvili

We report detection of oscillations in brightness temperature, size, and horizontal velocity of three small bright features in the chromosphere of a plage/enhanced-network region. The observations, which were taken with high temporal…

Context. An analysis of the oscillations above sunspots was carried out using simultaneous ground-based and Solar Dynamics Observatory (SDO) observations (SiI 10827A, HeI 10830A, FeI 6173A, 1700A, HeII 304A, FeIX 171A). Aims. Investigation…

Solar and Stellar Astrophysics · Physics 2014-11-25 N. I. Kobanov , A. A. Chelpanov , D. Y. Kolobov

We show that the coronal heating and the fast solar wind acceleration in the coronal holes are natural consequence of the footpoint fluctuations of the magnetic fields at the photosphere, by performing one-dimensional magnetohydrodynamical…

Astrophysics · Physics 2009-11-11 Takeru K. Suzuki , Shu-ichiro Inutsuka

Alfv\'en waves may be difficult to excite at the photosphere due to low ionization fraction and suffer near-total reflection at the transition region (TR). Yet they are ubiquitous in the corona and heliosphere. To overcome these…

Solar and Stellar Astrophysics · Physics 2015-06-04 Shelley C. Hansen , Paul S. Cally

The propagation and the evolution of Alfvenic pulses in the solar coronal arcades is investigated by means of MHD numerical simulations. Significant transverse oscillations in coronal loops, triggered by nearby flare events, are often…

Astrophysics · Physics 2009-11-10 Luca Del Zanna , Eveline Schaekens , Marco Velli

We present a new version of the Alfven Wave Solar Model (AWSoM), a global model from the upper chromosphere to the corona and the heliosphere. The coronal heating and solar wind acceleration are addressed with low-frequency Alfven wave…

Solar and Stellar Astrophysics · Physics 2015-06-17 Bart van der Holst , Igor V. Sokolov , Xing Meng , Meng Jin , Ward B. Manchester , Gabor Toth , Tamas I. Gombosi

The heating of the lower solar corona is examined using numerical simulations and theoretical models of magnetohydrodynamic turbulence in open magnetic regions. A turbulent energy cascade to small length scales perpendicular to the mean…

Astrophysics · Physics 2009-11-07 P. Dmitruk , W. H. Matthaeus , L. J. Milano , S. Oughton , G. P. Zank , D. J. Mullan

The Sun's surface vibrates in characteristic 5-minute oscillations, known as p-modes, generated by sound waves trapped within the convection zone. Although these oscillations have long been hypothesized to reach into the solar wind, direct…

The solar wind upstream of Mars's bow shock can be described in terms of Alfv\'enic turbulence, with an incompressible energy cascade rate of $10^{-17}$ J m$^{-3}$ s$^{-1}$ at magnetohydrodynamics (MHD) scales. The solar wind has more…

Solar and Stellar Astrophysics · Physics 2024-06-26 Norberto Romanelli , Christopher M. Fowler , Gina A. DiBraccio , Jared R. Espley , Jasper S. Halekas

Alfv\'enic waves are thought to play an important role in coronal heating and acceleration of solar wind. Here we investigated the statistical properties of Alfv\'enic waves along spicules (jets that protrude into the corona) in a polar…

Solar and Stellar Astrophysics · Physics 2015-05-28 Takenori J. Okamoto , Bart De Pontieu

Magnetic bright points in the solar photosphere, visible in both continuum and G-band images, indicate footpoints of kilogauss magnetic flux tubes extending to the corona. The power spectrum of bright-point motion is thus also the power…

Solar and Stellar Astrophysics · Physics 2017-11-29 Samuel J. Van Kooten , Steven R. Cranmer

Since their discovery, spicules have attracted increased attention as energy/mass bridges between the dense and dynamic photosphere and the tenuous hot solar corona. Mechanical energy of photospheric random and coherent motions can be…

Solar and Stellar Astrophysics · Physics 2015-05-13 T. V. Zaqarashvili , R. Erdelyi