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Related papers: Radiating Current Sheets in the Solar Chromosphere

200 papers

In the present paper, using MPI-AMRVAC, we perform a 2.5-D numerical MHD simulation of the dynamics and associated thermodynamical evolution of an initially force-free Harris current sheet subjected to an external velocity perturbation…

Solar and Stellar Astrophysics · Physics 2024-01-17 Sripan Mondal , Abhishek K Srivastava , David I. Pontin , Ding Yuan , Eric R. Priest

The mechanism by which the radiation received from obliquely rotating neutron stars is generated remains an open question half a century after the discovery of pulsars. In contrast, considerable progress has recently been made in…

High Energy Astrophysical Phenomena · Physics 2023-03-02 Houshang Ardavan

Strong gradients in plasma flows play a major role in space and astrophysical plasmas. A typical situation is that a static plasma equilibrium is surrounded by a plasma flow, which can lead to strong plasma flow gradients at the…

Solar and Stellar Astrophysics · Physics 2010-08-18 Dieter H. Nickeler , Thomas Wiegelmann

We investigate the importance of ambipolar diffusion and Hall currents for high-resolution comprehensive ('realistic') photospheric simulations. To do so we extended the radiative magnetohydrodynamics code \emph{MURaM} to use the…

Solar and Stellar Astrophysics · Physics 2015-06-04 Mark C. M. Cheung , Robert H. Cameron

We numerically study magnetic reconnection on different spatial scales and at different heights in the weakly ionized plasma of the low solar atmosphere (around $300-800$~km above the solar surface) within a reactive 2.5 D multi-fluid…

Solar and Stellar Astrophysics · Physics 2018-12-12 Lei Ni , Vyacheslav S. Lukin

Context. The recent discovery of much greater magnetic flux cancellation taking place at the photosphere than previously realised has led us in our previous works to suggest magnetic reconnection driven by flux cancellation as the cause of…

Solar and Stellar Astrophysics · Physics 2021-03-03 E. R. Priest , P. Syntelis

Following a CME which started on 2002 November 26, RHESSI, the Ramaty High Energy Solar Spectroscopic Imager, observed for 12 hours an X-ray source above the solar limb, at altitudes between 0.1 and 0.3 RS above the photosphere. The GOES…

Solar and Stellar Astrophysics · Physics 2015-06-03 Pascal Saint-Hilaire , Sam Krucker , Robert P. Lin

Relativistic current sheets have been proposed as the sites of dissipation in pulsar winds, jets in active galaxies and other Poynting-flux dominated flows. It is shown that the steady versions of these structures differ from their…

Astrophysics · Physics 2009-11-10 J. G. Kirk

Kinetic-scale current sheets observed in the solar wind are frequently approximately force-free despite the fact that their plasma $\beta$ is of the order of one. In-situ measurements have recently shown that plasma density and temperature…

Space Physics · Physics 2020-03-18 T. Neukirch , I. Y. Vasko , A. V. Artemyev , O. Allanson

Using high-resolution numerical simulations we investigate the plasma heating driven by periodic two-fluid acoustic waves that originate at the bottom of the photosphere and propagate into the gravitationally stratified and partially…

Solar and Stellar Astrophysics · Physics 2019-06-26 B. Kuźma , D. Wójcik , K. Murawski

The thickness of current sheets is extremely important, especially as it relates to the onset of fast magnetic reconnection. Onset determines how much magnetic free energy can build up in a field before it is explosively released. This has…

Solar and Stellar Astrophysics · Physics 2023-07-27 James A. Klimchuk , James E. Leake , Lars K. S. Daldorff , Craig D. Johnston

The solar chromosphere is weakly ionized and interactions between ionized particles and neutral particles likely have significant consequences for the thermodynamics of the plasma. We investigate the importance of introducing neutral…

Solar and Stellar Astrophysics · Physics 2015-06-04 Juan Martinez-Sykora , Bart De Pontieu , Viggo Hansteen

There is observational evidence that central compact objects (CCOs) in supernova remnants have moderately strong magnetic fields $B\sim10^{11}$ G. Meanwhile, available models of partially ionized hydrogen atmospheres of neutron stars with…

High Energy Astrophysical Phenomena · Physics 2014-12-03 A. Y. Potekhin , G. Chabrier , W. C. G. Ho

In this paper, we show a "proof of concept" of the heating mechanism of the solar chromosphere due to wave dissipation caused by the effects of partial ionization. Numerical modeling of non-linear wave propagation in a magnetic flux tube,…

Solar and Stellar Astrophysics · Physics 2016-03-16 S. Shelyag , E. Khomenko , A. de Vicente , D. Przybylski

We propose a mechanism for efficient heating of the solar chromosphere, based on non-ideal plasma effects. Three ingredients are needed for the work of this mechanism: (1) presence of neutral atoms; (2) presence of a non-potential magnetic…

Solar and Stellar Astrophysics · Physics 2012-02-13 Elena Khomenko , Manuel Collados

The temperature and density conditions in the magnetized photosphere and chromosphere of the Sun lead to a very small degree of atomic ionization. In addition, at particular height, the magnetic field may be strong enough to give rise to a…

Solar and Stellar Astrophysics · Physics 2015-04-08 Elena Khomenko

We have performed 3D radiation MHD simulations extending from the convection zone to the corona covering a box 16 Mm$^3$ at 32 km spatial resolution. The simulations show very fine structure in the chromosphere with acoustic shocks…

Solar and Stellar Astrophysics · Physics 2010-01-12 Mats Carlsson , Viggo H. Hansteen , Boris V. Gudiksen

We study the propagation and dissipation of magnetohydrodynamic waves in a set of numerical models that each include a solar--like stratified atmosphere and a magnetic field with a null point. All simulations have the same magnetic field…

Solar and Stellar Astrophysics · Physics 2019-07-24 Lucas A. Tarr , Mark Linton

In this paper, we study the energy conversion and spectra in a corona current sheet by 2.5-dimensional MHD numerical simulations. Numerical results show that many Petschek-like fine structures with slow-mode shocks mediated by plasmoid…

Solar and Stellar Astrophysics · Physics 2015-12-29 Lei Ni , Jun Lin , Zhixing Mei , Yan Li

Numerical models of solar flares typically focus on the behaviour of directly-heated flare models, adopting magnetic field- aligned, plane-parallel methodologies. With high spatial- and spectral-resolution ground-based optical observations…

Solar and Stellar Astrophysics · Physics 2022-09-21 Christopher M. J. Osborne , Lyndsay Fletcher