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Related papers: Coronal loop widths and pressure scale heights

200 papers

Solar prominences are long-lived cool and dense plasma curtains in the hot and rarefied outer solar atmosphere or corona. The physical mechanism responsible for their formation and especially for their internal plasma circulation has been…

Solar and Stellar Astrophysics · Physics 2016-05-25 Chun Xia , Rony Keppens

The Enthalpy Based Thermal Evolution of Loops (EBTEL) approximate model for static and dynamic coronal loops is developed to include the effect of a loop cross-sectional area which increases from the base of the transition region (TR) to…

Solar and Stellar Astrophysics · Physics 2021-11-19 P. J. Cargill , S. J. Bradshaw , J. A. Klimchuk , W. T. Barnes

Aims: Emission line profiles from solar coronal loops exhibit properties that are unexplained by current models. We investigate the non-thermal broadening associated with plasma heating in coronal loops that is induced by magnetic field…

Solar and Stellar Astrophysics · Physics 2020-08-28 D. I. Pontin , H. Peter , L. P. Chitta

The quiescent or dynamic nature of fine scale ray-like features in the sun corona, observed in visible light, is still an open question. Here, we show that most of daily and hourly periodic variations in visible light brightness of the high…

Solar and Stellar Astrophysics · Physics 2025-09-16 Nathalia Alzate , Simone Di Matteo

Stably-stratified layers may be present at the top of the electrically-conducting fluid layers of many planets either because the temperature gradient is locally subadiabatic or because a stable composition gradient is maintained by the…

Earth and Planetary Astrophysics · Physics 2022-11-08 Celine Guervilly

This work addresses the problem of plasma condensation and ``catastrophic cooling'' in solar coronal loops. We have carried out numerical calculations of coronal loops and find several classes of time-dependent solutions (static, periodic,…

Astrophysics · Physics 2009-11-10 D. A. N. Mueller , H. Peter , V. H. Hansteen

A single open magnetic flux tube spanning the solar photosphere (solar radius R) and the lower corona (R + 10 Mm) is modelled in magnetohydrostatic equilibrium within a realistic stratified atmosphere subject to solar gravity. Such flux…

Solar and Stellar Astrophysics · Physics 2014-06-16 Frederick Armstrong Gent , Viktor Fedun , Stuart John Mumford , Robertus Erdelyi

We perform MHD modeling of a single bright coronal loop to include the interaction with a non-uniform magnetic field. The field is stressed by random footpoint rotation in the central region and its energy is dissipated into heating by…

Solar and Stellar Astrophysics · Physics 2016-10-12 F. Reale , S. Orlando , M. Guarrasi , A. Mignone , G. Peres , A. W. Hood , E. R. Priest

We consider a model for thin liquid films in a rotating cylinder in the small surface tension limit. Using dynamical system methods, we show that the continuum of increasing shock solutions persists in the small surface tension limit,…

Fluid Dynamics · Physics 2015-03-17 Daniel Badali , Marina Chugunova , Dmitry Pelinovsky , Steven Pollack

Evolution of a coronal loop in response to an impulsive energy release is numerically modelled. It is shown that the loop density evolution curves exhibit quasi-periodic perturbations with the periods given approximately by the ratio of the…

Astrophysics · Physics 2009-11-10 V. M. Nakariakov , D. Tsiklauri , A. Kelly , T. D. Arber , M. J. Aschwanden

Context. The details of the spectral profiles of extreme UV emission lines from solar active regions contain key information to investigate the structure, dynamics, and energetics of the solar upper atmosphere. Aims. We characterize the…

Solar and Stellar Astrophysics · Physics 2019-06-19 Leping Li , Hardi Peter

Kink oscillations are frequently observed in coronal loops. This work aims to numerically clarify the influence of loop curvature on horizontally and vertically polarized kink oscillations. Working within the framework of ideal MHD, we…

Solar and Stellar Astrophysics · Physics 2024-04-09 Mingzhe Guo , Tom Van Doorsselaere , Bo Li , Marcel Goossens

A system of multiple open magnetic flux tubes spanning the solar photosphere and lower corona is modelled analytically, within a realistic stratified atmosphere subject to solar gravity. This extends results for a single magnetic flux tube…

Solar and Stellar Astrophysics · Physics 2014-07-18 Frederick A. Gent , Viktor Fedun , Rebertus Erd'elyi

We present results from 3D visco-resistive magnetohydrodynamic (MHD) simulations of the emergence of a convection zone magnetic flux tube into a solar atmosphere containing a pre-existing dipole coronal field, which is orientated to…

Solar and Stellar Astrophysics · Physics 2015-06-17 James E. Leake , Mark G. Linton , Tibor Török

We use time-series ultraviolet full sun images to construct limb-synoptic maps of the Sun. On these maps, large-scale, long-lived coronal streamers appear as repetitive sinusoid-like arcs projected over the polar regions. They are caused by…

Solar and Stellar Astrophysics · Physics 2015-05-28 Jing Li

Meridional circulation regulates the Sun's interior dynamics and magnetism. While it is well accepted that meridional flows are poleward at the Sun's surface, helioseismic observations have yet to provide a definitive answer for the depth…

Fluids at supercritical pressures exhibit large variations in density near the pseudo critical line, such that buoyancy plays a crucial role in their fluid dynamics. Here, we experimentally investigate heat transfer and turbulence in…

Fluid Dynamics · Physics 2025-06-11 Marko Draskic , Jerry Westerweel , Rene Pecnik

Coronal loops act as resonant cavities for low frequency fluctuations that are transmitted from the deeper layers of the solar atmosphere and are amplified in the corona, triggering nonlinear interactions. However trapping is not perfect,…

Solar and Stellar Astrophysics · Physics 2015-06-03 Andrea Verdini , Roland Grappin , Marco Velli

Using a thin flux tube model in a rotating spherical shell of turbulent, solar-like convective flows, we find that the distribution of emerging flux tubes in our simulation is inhomogeneous in longitude, with properties similar to those of…

Solar and Stellar Astrophysics · Physics 2015-06-15 Maria A. Weber , Yuhong Fan , Mark S. Miesch

A recently proposed schematic model for the non--linear rheology of dense colloidal dispersions is compared to flow curves measured in suspensions that consist of thermosensitive particles. The volume fraction of this purely repulsive model…

Soft Condensed Matter · Physics 2009-11-11 Matthias Fuchs , Matthias Ballauff