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Related papers: High frequency waves in the corona due to null poi…

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Solar coronal waves frequently appear as bright disturbances that propagate globally from the eruption center in the solar atmosphere, just like the tsunamis in the ocean on Earth. Theoretically, coronal waves can sweep over the underlying…

Rapidly decaying long-period oscillations often occur in hot coronal loops of active regions associated with small (or micro-) flares. This kind of wave activity was first discovered with the SOHO/SUMER spectrometer from Doppler velocity…

Solar and Stellar Astrophysics · Physics 2021-10-01 Tongjiang Wang , Leon Ofman , Ding Yuan , Fabio Reale , Dmitrii Y. Kolotkov , Abhishek K. Srivastava

The quiet solar corona emits meter-wave thermal bremsstrahlung. Coronal radio emission can only propagate above that radius, $R_\omega$, where the local plasma frequency eqals the observing frequency. The radio interferometer LOw Frequency…

Solar and Stellar Astrophysics · Physics 2018-06-13 C. Vocks , G. Mann , F. Breitling , M. M. Bisi , B. Dabrowski , R. Fallows , P. T. Gallagher , A. Krankowski , J. Magdalenic , C. Marque , D. Morosan , H. Rucker

Coronal waves, significant solar phenomena, act as diagnostic tools for scientists studying solar atmosphere properties. Here, we present a novel observation detailing how a coronal wave event, associated with an X5.0 class flare,…

We use images of high spatial, spectral and temporal resolution, obtained using both ground- and space-based instrumentation, to investigate the coupling between wave phenomena observed at numerous heights in the solar atmosphere. Intensity…

Solar and Stellar Astrophysics · Physics 2015-06-11 D. B. Jess , I. De Moortel , M. Mathioudakis , D. J. Christian , K. P. Reardon , P. H. Keys , F. P. Keenan

We performed 2.5D magnetohydrodynamic (MHD) simulations showing the propagation of fast-mode MHD waves of different initial amplitudes and their interaction with a coronal hole (CH), using our newly developed numerical code. We find that…

Recurrent and propagating intensity perturbations are frequently observed in extreme ultraviolet (EUV) channels along coronal fan loops above sunspots, and these perturbations are suggested to be slow magnetoacoustic waves. Numerous studies…

Solar and Stellar Astrophysics · Physics 2025-02-26 Junwei Zhao , Tongjiang Wang , Ruizhu Chen

Recent observations revealed that the solar atmosphere is highly structured in density, temperature and magnetic field. The presence of these gradients may lead to the appearance of currents in the plasma, which in the weakly collisional…

Astrophysics · Physics 2009-11-13 R. Mecheri , E. Marsch

The aim of this work is to study the energy transport by means of MHD waves propagating in quiet Sun magnetic topology from layers below the surface to the corona. Upward propagating waves find obstacles, such as the equipartition layer…

Solar and Stellar Astrophysics · Physics 2015-05-13 Irantzu C. Santamaria , Elena Khomenko , Manuel Collados

In the lower solar atmosphere, the chromosphere is permeated by jets known as spicules, in which plasma is propelled at speeds of 50 to 150 kilometers per second into the corona. The origin of the spicules is poorly understood, although…

To study the dynamics of coronal holes and the role of waves in the acceleration of the solar wind, spectral observations were performed over polar coronal hole regions with the SUMER spectrometer on SoHO and the EIS spectrometer on Hinode.…

Solar and Stellar Astrophysics · Physics 2009-05-08 D. Banerjee , L. Teriaca , G. R. Gupta , S. Imada , G. Stenborg , S. K. Solanki

During solar flares a large amount of electrons with energies greater than 20 keV is generated with a production rate of typically $10^{36}$ s$^{-1}$. A part of them is able to propagate along open magnetic field lines through the corona…

Solar and Stellar Astrophysics · Physics 2015-11-11 F. Breitling , G. Mann , C. Vocks

Arch-like loop structures filled with million Kelvin hot plasma form the building blocks of the quiet-Sun corona. Both high-resolution observations and magnetoconvection simulations show the ubiquitous presence of magnetic fields on the…

Interfacial waves arising in a two-phase swirling flow driven by a low-frequency rotating magnetic field (RMF) are studied. At low RMF frequencies, of the order of 1-10 Hz, the oscillatory part of the induced Lorenz force becomes comparable…

Fluid Dynamics · Physics 2024-01-09 Gerrit Maik Horstmann , Yakov Nezihovski , Thomas Gundrum , Alexander Gelfgat

Coronal fan loops rooted in sunspot umbra show outward propagating waves with subsonic phase speed and period around 3-min. However, their source region in the lower atmosphere is still ambiguous. We performed multi-wavelength observations…

Solar and Stellar Astrophysics · Physics 2023-09-06 Ananya Rawat , Girjesh Gupta

The magnetic switchbacks observed recently by the Parker Solar Probe have raised the question about their nature and origin. One of the competing theories of their origin is the interchange reconnection in the solar corona. In this…

Solar and Stellar Astrophysics · Physics 2021-06-23 Norbert Magyar , Dominik Utz , Robertus Erdélyi , Valery M. Nakariakov

High frequency oscillations are observed in a neon plasma of a direct current magnetron discharge. At low discharge currents, we see highly coherent 60 MHz fluctuations. Above a distinct current threshold, secondary 5 - 10 MHz fluctuations…

Plasma Physics · Physics 2024-05-07 Ryan C. Przybocki , Mark A. Cappelli

We study the propagation properties of slow magneto-acoustic waves in a multi-thermal coronal loop using a 3D MHD model, for the first time. A bundle of 33 vertical cylinders, each of 100{\,}km radius, randomly distributed over a circular…

Solar and Stellar Astrophysics · Physics 2024-06-06 S. Krishna Prasad , T. Van Doorsselaere

Coronal holes are the dark patches in the solar corona associated with relatively cool, less dense plasma and unipolar fields. The fast component of the solar wind emanates from these regions. Several observations reveal the presence of…

Solar and Stellar Astrophysics · Physics 2016-03-09 D. Banerjee , S. Krishna Prasad