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Related papers: Coronal loop widths and pressure scale heights

200 papers

We examine the role of stratification in determining the scale for turbulent anelastic convection. Motivated by the range of scales observed in convection at the solar photosphere, we perform local numerical simulations of convection for a…

Solar and Stellar Astrophysics · Physics 2019-04-03 M. Kessar , D. W. Hughes , E. Kersale , K. A. Mizerski , S. M. Tobias

Despite decades of studying the Sun, the coronal heating problem remains unsolved. One fundamental issue is that we do not know the spatial scale of the coronal heating mechanism. At a spatial resolution of 1000 km or more it is likely that…

Solar and Stellar Astrophysics · Physics 2012-06-07 David H. Brooks , Harry P. Warren , Ignacio Ugarte-Urra

Large regions of giant planets are thought to possess unstable thermal gradients stabilised by gradients in heavy-element composition. The fluid can then develop semi-convection, a double-diffusive instability driven by the unequal…

Fluid Dynamics · Physics 2026-05-27 Paul Pružina , Nathanaël Schaeffer , David Cébron

This paper reviews the latest observational evidence for the existence of propagating waves in the open magnetic flux tubes of the solar corona. SOHO measurements have put tentative limits on the fluxes of various types of…

Astrophysics · Physics 2007-05-23 Steven R. Cranmer

The Sun provides us with the only spatially well-resolved astrophysical example of turbulent thermal convection. While various aspects of solar photospheric turbulence, such as granulation (one-Megameter horizontal scale), are well…

Solar and Stellar Astrophysics · Physics 2017-03-14 F. Rincon , T. Roudier , A. A. Schekochihin , M. Rieutord

A recent analysis has suggested that the heating of plasma loops in the solar corona depends not just on the Poynting flux but also on processes yet to be identified. This discovery reflects and refines earlier questions such as, why and…

Solar and Stellar Astrophysics · Physics 2024-08-16 P. G. Judge , N. P. M. Kuin

Coronal holes (CH) emit significantly less at coronal temperatures than quiet-Sun regions (QS), but can hardly be distinguished in most chromospheric and lower transition region lines. A key quantity for the understanding of this phenomenon…

Astrophysics · Physics 2009-06-25 T. Wiegelmann , S. K. Solanki

Direct numerical simulations are conducted to study the receptivity and transition mechanisms in a solitary wave boundary layer developing over randomly organized wave-like bottom topography. The boundary layer flow shows a selective…

Fluid Dynamics · Physics 2021-02-24 Asim Önder , Philip L. -F. Liu

There are ubiquitous flows observed in the solar atmosphere of sub-Alfv\'{e}nic speeds, however after flaring and coronal mass ejection events flows can become Alfv\'{e}nic. In this Letter, we derive an expression for the standing kink mode…

Solar and Stellar Astrophysics · Physics 2015-05-27 J. Terradas , I. Arregui , G. Verth , M. Goossens

This paper reviews our growing understanding of the physics behind coronal heating (in open-field regions) and the acceleration of the solar wind. Many new insights have come from the last solar cycle's worth of observations and theoretical…

Solar and Stellar Astrophysics · Physics 2010-02-02 Steven R. Cranmer , John L. Kohl , Mari Paz Miralles , Adriaan A. van Ballegooijen

Potential Field Source Surface (PFSS) models are widely used to study the solar corona and form the basis for solar wind forecasting, yet often fail to reproduce observed properties of coronal holes. We analyze 702 observed coronal holes…

Solar and Stellar Astrophysics · Physics 2026-01-19 Stephan G. Heinemann , Jens Pomoell , Manuela Temmer

The origin of solar transition region redshifts is not completely understood. Current research is addressing this issue by investigating three-dimensional magneto-hydrodynamic models that extend from the photosphere to the corona. By…

Solar and Stellar Astrophysics · Physics 2015-05-28 Pia Zacharias , Sven Bingert , Hardi Peter

The solar corona produces coronal rain, hundreds of times colder and denser material than the surroundings. Coronal rain is known to be deeply linked to coronal heating, but its origin, dynamics, and morphology are still not well…

Solar and Stellar Astrophysics · Physics 2023-07-05 Seray Şahin , Patrick Antolin , Clara Froment , Thomas A. Schad

Observations show that transverse magnetohydrodynamic (MHD) waves and flows are often simultaneously present in magnetic loops of the solar corona. The waves are resonantly damped in the Alfv\'en continuum because of plasma and/or magnetic…

Solar and Stellar Astrophysics · Physics 2019-03-06 Roberto Soler

We argue that the magnetically closed corona evolves primarily quasi-statically, punctuated by many localized bursts of activity associated with magnetic reconnection at a myriad of small current sheets. The sheets form by various processes…

Solar and Stellar Astrophysics · Physics 2021-05-27 James A. Klimchuk , Spiro K. Antiochos

The stress versus strain curves in dense colloidal dispersions under start-up shear flow are investigated combining experiments on model core-shell microgels, computer simulations of hard disk mixtures, and mode coupling theory. In dense…

The Sun is the only star that we can spatially resolve and it can be regarded as a fundamental plasma laboratory of astrophysics. The solar transition region (TR), the layer between the solar chromosphere and corona, plays an important role…

Solar and Stellar Astrophysics · Physics 2013-05-13 Hui Tian , Eckart Marsch , Chuanyi Tu , Werner Curdt , Jiansen He

Oscillations are abundant in the solar corona. Coronal loop oscillations are typically studied using highly idealised models of magnetic flux tubes. In order to improve our understanding of coronal oscillations, it is necessary to consider…

Solar and Stellar Astrophysics · Physics 2023-08-02 P. Kohutova , P. Antolin , M. Szydlarski , M. Carlsson

Surface granulation of the Sun is primarily a consequence of thermal transport in the outer 1 % of the radius. Its typical scale of about 1 - 2 Mm is set by the balance between convection, free-streaming radiation, and the strong density…

Solar and Stellar Astrophysics · Physics 2015-06-18 Shravan M. Hanasoge , Katepalli R. Sreenivasan

The scaling laws which relate the peak temperature $T_M$ and volumetric heating rate $E_H$ to the pressure $P$ and length $L$ for static coronal loops were established over 40 years ago; they have proved to be of immense value in a wide…

Solar and Stellar Astrophysics · Physics 2020-12-09 Stephen J. Bradshaw , A. Gordon Emslie