Related papers: Cross Sections of Coronal Loop Flux Tubes
We present a series of numerical simulations aimed at understanding the nature and origin of turbulence in coronal loops in the framework of the Parker model for coronal heating. A coronal loop is studied via reduced magnetohydrodynamics…
Understanding the relationship between the magnetic field and coronal heating is one of the central problems of solar physics. However, studies of the magnetic properties of impulsively heated loops have been rare. We present results from a…
Fast rotating cool stars are characterised by high magnetic activity levels and frequently show dark spots up to polar latitudes. Their distinctive surface distributions of magnetic flux are investigated in the context of the solar-stellar…
Twisted coronal loops should be ubiquitous in the solar corona. Twisted magnetic fields contain excess magnetic energy, which can be released during magnetic reconnection, causing solar flares. The aim of this work is to investigate…
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,…
Context: The location of coronal heating in magnetic loops has been the subject of a long-lasting controversy: does it occur mostly at the loop footpoints, at the top, is it random, or is the average profile uniform? Aims: We try to address…
Magnetic flux ropes are a key component of coronal mass ejections, forming the core of these eruptive phenomena. However, determining whether a flux rope is present prior to eruption onset and, if so, the rope's handedness and the number of…
It is shown that if a current-carrying magnetic flux tube is bulged at its axial midpoint z=0 and constricted at its axial endpoints z=+h,-h, then plasma will be accelerated from z=+h,-h towards z=0 resulting in a situation similar to two…
As the observational signature of the footprints of solar magnetic field lines open into the heliosphere, coronal holes provide a critical measure of the structure and evolution of these lines. Using a combination of Solar and Heliospheric…
We present numerical models from the field-aligned Hydrodynamics and Radiation Code (HYDRAD) of a highly asymmetric closed coronal loop with near-singular expansion factor. This loop was chosen to simulate a coronal magnetic flux tube that…
The most probable initial magnetic configuration of a CME is a flux rope consisting of twisted field lines which fill the whole volume of a dark coronal cavity. The flux ropes can be in stable equilibrium in the coronal magnetic field for…
We study non-axisymmetric oscillations of a straight magnetic tube with an elliptic cross-section and density varying along the tube. The governing equations for kink and fluting modes in the thin tube approximation are derived. We found…
We study transverse fast magnetohydrodynamic waves in a system of two coronal loops modeled as smoothed, dense plasma cylinders in a uniform magnetic field. The collective oscillatory properties of the system due to the interaction between…
The expansion of coronal loops in the transition region may considerably influence the diagnostics of the plasma emission measure. The cross sectional area of the loops is expected to depend on the temperature and pressure, and might be…
Magnetic flux ropes within interplanetary coronal mass ejections are often characterized as simplistic cylindrical or toroidal tubes with field lines that twist around the cylinder or torus axis. Recent multi-point observations suggest that…
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…
Context. Photospheric motions shuffle the footpoints of the strong axial magnetic field that threads coronal loops giving rise to turbulent nonlinear dynamics characterized by the continuous formation and dissipation of field-aligned…
We have expanded upon earlier work that investigates the relative importance of coronal loops with isothermal $versus$ multithermal cross-field temperature distributions. These results are important for determining if loops have…
The emergence of magnetic flux from the convection zone into the corona is an important process for the dynamical evolution of the coronal magnetic field. In this paper we extend our previous numerical investigations, by looking at the…
Coronal loops in active regions are the subjects of intensive investigation, but the important diffuse 'unresolved' emission in which they are embedded has received relatively little attention. Here we measure the densities and emission…