English
Related papers

Related papers: Magnetohydrodynamic Non-linearities in Sunspot Atm…

200 papers

Magnetic reconnection at small spatial scales is a fundamental driver of energy release and plasma dynamics in the lower solar atmosphere. We present observations of a brightening in an active region, captured in high-resolution data from…

Solar and Stellar Astrophysics · Physics 2025-04-14 J. M. da Silva Santos , E. Dunnington , R. Jarolim , S. Danilovic , S. Criscuoli

Magnetic flux emergence into the outer layers of the Sun is a fundamental mechanism for releasing energy into the chromosphere and the corona. In this paper, we study the emergence of granular-sized flux concentrations and the structuring…

Solar and Stellar Astrophysics · Physics 2015-09-23 Jaime de la Cruz Rodríguez , Viggo Hansteen , Luis Bellot-Rubio , Ada Ortiz

Slow magnetoacoustic waves (SMAWs) have been considered in the past as a possible candidate for chromospheric heating. This study analyzes 20 active regions observed between 2012 and 2016 to examine the amplitude and energy flux variation…

Solar and Stellar Astrophysics · Physics 2025-04-22 Y. Sanjay , S. Krishna Prasad , P. S. Rawat

The elemental composition of the Sun's hot atmosphere, the corona, shows a distinctive pattern that is different than the underlying surface, or photosphere (Pottasch 1963). Elements that are easy to ionize in the chromosphere are enhanced…

Solar and Stellar Astrophysics · Physics 2022-05-18 David H. Brooks , Deborah Baker , Lidia van Driel-Gesztelyi , Harry P. Warren , Stephanie L. Yardley

We analyze a grid of radiative hydrodynamic simulations of solar flares to study the energy balance and response of the atmosphere to nonthermal electron beam heating. The appearance of chromospheric bubbles is one of the most notable…

Solar and Stellar Astrophysics · Physics 2020-05-22 Aaron Reid , Bogdan Zhigulin , Mats Carlsson , Mihalis Mathioudakis

We present a study of wave processes in the sunspot region NOAA 12670 on 2017 August 10 observed by the Goode Solar Telescope in the TiO 7057 A and Ha 6563 A spectral lines. To study the distribution of power oscillations and their…

Solar and Stellar Astrophysics · Physics 2020-01-15 Robert Sych , Yuzef Zhugzhda , Xiaoli Yan

Magnetic reconnection plays a crucial role in the energy release process for different kinds of solar eruptions and activities. The rapid solar eruption requires a fast reconnection model. Plasmoid instability in the reconnecting current…

Solar and Stellar Astrophysics · Physics 2024-05-01 Guanchong Cheng , Lei Ni , Zehao Tang , Yajie Chen , Yuhao Chen , Jialiang Hu , Jun Lin

The heating and structure of the solar chromosphere depends on the underlying magnetic field, among other parameters. The lowest magnetic flux of the solar atmosphere is found in the quiet Sun internetwork and is thought to be provided by…

Solar and Stellar Astrophysics · Physics 2025-11-19 D. Przybylski , R. Cameron , S. K. Solanki , M. Rempel , S. Danilovic , J. Leenaarts

Shocks waves are a ubiquitous feature of many astrophysical plasma systems, and an important process for energy dissipation and transfer. The physics of these shock waves are frequently treated/modeled as a collisional, fluid MHD…

Plasma Physics · Physics 2021-11-17 Colby C. Haggerty , Antoine Bret , Damiano Caprioli

This short paper reviews several recent key observations of the processes occurring in the lower atmosphere (chromosphere and photosphere) during flares. These are: evidence for compact and fragmentary structure in the flare chromosphere,…

Solar and Stellar Astrophysics · Physics 2013-12-02 Lyndsay Fletcher , Paulo J. A. Simoes

The analysis of the spectral properties and dynamic evolution of a CME/shock event observed on November 1st 2003 in white-light by the LASCO coronagraph and in the ultraviolet by the UVCS instrument operating aboard SOHO, has been performed…

Solar and Stellar Astrophysics · Physics 2012-11-20 Carlo Benna , Salvatore Mancuso , Silvio Giordano , Lorenzo Gioannini

Solar prominences are cool 10$^4$ Kelvin plasma clouds supported in the surrounding 10$^6$ Kelvin coronal plasma by as-yet undetermined mechanisms. Observations from \emph{Hinode} show fine-scale threadlike structures oscillating in the…

Interplanetary shocks are fundamental constituents of the heliosphere, where they form as a result of solar activity. We use previously unavailable measurements of interplanetary shocks in the inner heliosphere provided by Solar Orbiter,…

Numerical simulations of the solar chromosphere predict a diverse thermal structure with both hot and cool regions. Observations of plage regions in particular feature broader and brighter chromospheric lines, which suggest that they are…

Solar and Stellar Astrophysics · Physics 2020-02-12 J. M. da Silva Santos , J. de la Cruz Rodríguez , J. Leenaarts , G. Chintzoglou , B. De Pontieu , S. Wedemeyer , M. Szydlarski

Sunspots on the surface of the Sun are the observational signatures of intense manifestations of tightly packed magnetic field lines, with near-vertical field strengths exceeding 6,000 G in extreme cases. It is well accepted that both the…

Magnetic reconnection is a fundamental physical process that can drive rapid conversion of magnetic energy into plasma bulk flows, thermal heating, and particle acceleration in space and astrophysical plasmas. Classical reconnection theory…

We present a model of magnetohydrodynamic (MHD) turbulence in the extended solar corona that contains the effects of collisionless dissipation and anisotropic particle heating. Measurements made by UVCS/SOHO have revived interest in the…

Astrophysics · Physics 2009-11-07 S. R. Cranmer , A. A. van Ballegooijen

Recent Sunrise/IMaX observations have revealed the existence of supersonic magnetic flows. Our aim is to determine the origin of such flows by using realistic MHD simulations. We simulate cancellation and emergence of magnetic flux through…

Solar and Stellar Astrophysics · Physics 2015-06-22 S. Danilovic , R. H. Cameron , S. K. Solanki

In this paper, weak turbulence theory is used to investigate the nonlinear evolution of the parametric instability in 3D low-$\beta$ plasmas at wavelengths much greater than the ion inertial length under the assumption that slow…

Space Physics · Physics 2018-03-14 Benjamin D. G. Chandran

We present an interpretation of the recent Daniel K. Inouye Solar Telescope (DKIST) observations of propagating wavefronts in the lower solar atmosphere. Using MPS/University of Chicago MHD (MURaM) radiative magnetohydrodynamic simulations…