Related papers: Cross Sections of Coronal Loop Flux Tubes
In a recent letter (ApJ 517, L155) Lenz et al. have shown the evidence of uniform temperature along steady long coronal loops observed by TRACE in two different passbands (171 A and 195 A filters). We propose that such an evidence can be…
I report on observations of a set of magnetic loops above a region with late-phase flux emergence taken by IRIS, Hinode and SDO. The loop system consists of many transition region loop threads with size of 5--12\arcsec\ in length and…
Quasi-periodic intensity disturbances propagating upward along the coronal structure have been extensively studied using EUV imaging observations from SOHO/EIT and TRACE. They were interpreted as either slow mode magnetoacoustic waves or…
The coronal magnetic field is the primary driver of solar dynamic events. Linear and circular polarization signals of certain infrared coronal emission lines contain information about the magnetic field, and to access this information,…
Magnetic clouds (MCs) are observed insitu by spacecraft. The rotation of their magnetic field is typically interpreted as the crossing of a twisted magnetic flux tube, or flux rope, which was launched from the solar corona. The detailed…
We apply a new method to determine the magnetic field in coronal loops using observations of coronal loop oscillations. We analyze seven Doppler shift oscillation events detected by SUMER in the hot flare line Fe XIX to obtain oscillation…
Efficient radiation at second and/or higher harmonics of Wce has been suggested to circumvent the escaping difficulty of the electron cyclotron maser emission mechanism when it is applied to solar radio bursts, such as spikes. In our…
Any successful model of coronal loops must explain a number of observed properties. For warm (~ 1 MK) loops, these include: 1. excess density, 2. flat temperature profile, 3. super-hydrostatic scale height, 4. unstructured intensity…
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…
The outer atmosphere of the Sun is composed of plasma heated to temperatures well in excess of the visible surface. We investigate short cool and warm (<1 MK) loops seen in the core of an active region to address the role of field-line…
How and where are coronal loops rooted in the solar lower atmosphere? The details of the magnetic environment and its evolution at the footpoints of coronal loops are crucial to understanding the processes of mass and energy supply to the…
Observations reveal a correspondence between chromospheric type II spicules and bright upwardly moving fronts in the corona observed in the EUV band. However, theoretical considerations suggest that these flows are unlikely to be the main…
Two recent works have analyzed a solar large and steady coronal loop observed with Yohkoh/SXT in two filter passbands to infer the distribution of the heating along it. Priest et al. (2000) modelled the distribution of the temperature…
Context: The expansion of network magnetic fields with height is a fundamental property of flux tube models. A rapid expansion is required to form a magnetic canopy. Aims: We characterize the observed expansion properties of magnetic…
Coronal loops, constituting the basic building blocks of the active Sun, serve as primary targets to help understand the mechanisms responsible for maintaining multi-million Kelvin temperatures in the solar and stellar coronae. Despite…
Coronal loop emission profiles are often of remarkably constant width along their entire lengths, contradicting expectations based on model coronal magnetic field strengths decreasing with height. Meanwhile Paul Bellan has produced a…
Coronal loops are the basic building block of the upper solar atmosphere. Comprehending how these are energized, structured, and evolve is key to understanding stellar coronae. Here we investigate how the energy to heat the loop is…
Coronal hole boundaries are the interfaces between closed and open magnetic field regions in the solar atmosphere. Many fundamental processes take place at these regions, including magnetic reconnection that is responsible for solar wind…
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…
We aim to study the influence of radiative cooling on the standing kink oscillations of a coronal loop. Using the FLASH code, we solved the 3D ideal magnetohydrodynamic equations. Our model consists of a straight, density enhanced and…