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Related papers: Magnetohydrodynamic Non-linearities in Sunspot Atm…

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Transverse MHD waves permeate the solar atmosphere and are a candidate for coronal heating. However, the origin of these waves is still unclear. In this work, we analyse coordinated observations from \textit{Hinode}/SOT and \textit{IRIS} of…

Solar and Stellar Astrophysics · Physics 2018-07-25 Patrick Antolin , Paolo Pagano , Ineke De Moortel , Valery M. Nakariakov

Coronal loops trace out bipolar, arch-like magnetic fields above the Sun's surface. Recent measurements that combine rotational tomography, extreme ultraviolet imaging, and potential-field extrapolation have shown the existence of large…

Solar and Stellar Astrophysics · Physics 2016-11-15 Avery J. Schiff , Steven R. Cranmer

We investigate the emergence of magnetic flux in the quiet Sun at very small spatial scales, focusing on the magnetic connection between the photosphere and chromosphere. The observational data consist of spectropolarimetric measurements…

Solar and Stellar Astrophysics · Physics 2009-07-22 M. J. Martinez Gonzalez , L. R. Bellot Rubio

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

Magnetized oblique shocks are of interest in various plasmas, including in astrophysical systems, magneto-inertial confinement fusion experiments, and in aerospace applications. Through experiments on the COBRA pulsed power facility…

Plasma ions heating (especially minor heavy ions preferential heating) in fast solar wind and solar corona is an open question in space physics. However, Alfv\'en waves have been always considered as a candidate of energy source for corona…

Plasma Physics · Physics 2021-08-17 Peng He

Context. The origin of the heating of the solar atmosphere is still an unsolved problem. As the photosphere and chromosphere radiate more energy than the solar corona, it is challenging but important to reveal all the mechanisms that…

Solar and Stellar Astrophysics · Physics 2021-08-25 R. Niedziela , K. Murawski , S. Poedts

Super-Alfv\'enic jets, with kinetic energy densities significantly exceeding that of the solar wind, are commonly generated downstream of Earth's bow shock under both high and low beta plasma conditions. In this study, we present…

Space Physics · Physics 2024-08-16 Adnane Osmane , Savvas Raptis

Two well known turbulent dynamo and MHD oscillation mechanisms are critically examined and fundamental difficulties are presented. Following new ideas on the genesis of the solar cycle and activity phenomena are presented. Inevitability of…

Solar and Stellar Astrophysics · Physics 2009-09-25 K. M. Hiremath

Magnetohydrodynamic (MHD) plasma turbulence is believed to play a vital role in the production of energetic electrons during solar flares and the non-thermal broadening of spectral lines is a key sign of this turbulence. Here, we determine…

Solar and Stellar Astrophysics · Physics 2021-12-22 Morgan Stores , Natasha L. S. Jeffrey , Eduard P. Kontar

UV bursts and Ellerman bombs are transient brightenings observed in the low solar atmospheres of emerging flux regions. Observations have discovered the cospatial and cotemporal EBs and UV bursts, and their formation mechanisms are still…

Solar and Stellar Astrophysics · Physics 2021-02-17 Lei Ni , Yajie Chen , Hardi Peter , Hui Tian , Jun Lin

The problem of solar chromospheric heating remains a challenging one with wider implications for stellar physics. Several studies in the recent past have shown that small-scale inclined magnetic field elements channel copious amount of…

Solar and Stellar Astrophysics · Physics 2018-12-14 S. P. Rajaguru , C. R. Sangeetha , Durgesh Tripathi

Solar chromosphere consists of a partially ionized plasma, which makes modeling the solar chromosphere a particularly challenging numerical task. Here we numerically model chromospheric waves using a two-fluid approach with a newly…

Solar and Stellar Astrophysics · Physics 2019-08-15 B. Popescu Braileanu , V. S. Lukin , E. Khomenko , A. de Vicente

The recent rediscovery of magnetic field switchbacks or deflections embedded in the solar wind flow by the Parker Solar Probe mission lead to a huge interest in the modelling of the formation mechanisms and origin of these switchbacks.…

Solar and Stellar Astrophysics · Physics 2021-04-28 Norbert Magyar , Dominik Utz , Robertus Erdélyi , Valery M. Nakariakov

Sunspots host a large variety of oscillatory phenomena, whose properties depend on the nature of the wave modes and the magnetic and thermodynamic structure of the spot. Umbral chromospheric oscillations exhibit significant differences…

Solar and Stellar Astrophysics · Physics 2020-07-22 T. Felipe

One of the striking observations from the Parker Solar Probe (PSP) spacecraft is the prevalence in the inner heliosphere of large amplitude, Alfv\'enic magnetic field reversals termed 'switchbacks'. These $\delta B_R/B \sim \mathcal{O}(1$)…

In sunspot umbrae, the core of some chromospheric lines exhibits periodic brightness enhancements known as umbral flashes. The consensus is that they are produced by the upward propagation of shock waves. This view has recently been…

Aims. To understand the morphology of the chromosphere in sunspot umbra. We investigate if the horizontal structures observed in the spectral core of the Ca II H line are ephemeral visuals caused by the shock dynamics of more stable…

Solar and Stellar Astrophysics · Physics 2015-02-11 V. M. J. Henriques , E. Scullion , M. Mathioudakis , D. Kiselman , P. T. Gallagher , F. P. Keenan

We aim to identify the physical processes which occur in the magnetic network of the chromosphere and which contribute to its dynamics and heating. Specifically, we study the propagation of transverse (kink) MHD waves which are impulsively…

Astrophysics · Physics 2009-11-10 S. S. Hasan , P. Ulmschneider

The solar corona and young solar wind may be characterized by critical surfaces -- the sonic, Alfv\'en, and first plasma-$\beta$ unity surfaces -- that demarcate regions where the solar wind flow undergoes certain crucial transformations.…

Solar and Stellar Astrophysics · Physics 2019-03-20 Rohit Chhiber , Arcadi V. Usmanov , William H. Matthaeus , Melvyn L. Goldstein