The Library
Dynamics of plasma condensations in a gravitationally stratified coronal loop
Tools
Kohutova, Petra and Verwichte, E. (Erwin) (2017) Dynamics of plasma condensations in a gravitationally stratified coronal loop. Astronomy & Astrophysics, 602 . A23. doi:10.1051/0004-6361/201629912 ISSN 0004-6361.
|
PDF
WRAP-dynamics-plasma-condensations-gravitationally-loop-Verwichte-2018.pdf - Published Version - Requires a PDF viewer. Available under License Creative Commons Attribution 4.0. Download (838Kb) | Preview |
|
|
PDF
WRAP-dynamics-plasma-loop-Kohutova-2017.pdf - Accepted Version - Requires a PDF viewer. Download (1096Kb) | Preview |
Official URL: http://dx.doi.org/10.1051/0004-6361/201629912
Abstract
Context
Coronal rain composed of cool plasma condensations falling from coronal heights is a phenomenon occurring in footpoint-heated coronal loops as a result of thermal instability. High-resolution coronal rain observations suggest that condensations move with less than free-fall speed and can sometimes undergo longitudinal oscillations.
Aims
We investigate the evolution and dynamics of plasma condensations in a gravitationally stratified coronal loop.
Methods
We carried out 2.5 dimensional magnetohydrodynamic simulations of a cool plasma condensation in a gravitationally stratified coronal loop and analysed its evolution, kinematics, and the evolution of the forces acting on the condensation. We further propose a one-dimensional analytical model of the condensation dynamics.
Results
The motion of plasma condensations is found to be strongly affected by the pressure of the coronal loop plasma. Maximum downward velocities are in agreement with recent coronal rain observations. A high coronal magnetic field or low condensation mass can lead to damped oscillatory motion of the condensations that are caused by the pressure gradient force and magnetic tension force that results from bending of the magnetic field in the lower part of the coronal loop. Period and damping scaling time of the oscillatory motion seen in the simulations are consistent with values predicted by the model.
Conclusions
The combined effect of pressure gradients in the coronal loop plasma and magnetic tension force that results from changes in magnetic field geometry can explain observed sub-ballistic motion and longitudinal oscillations of coronal rain
Item Type: | Journal Article | |||||||||
---|---|---|---|---|---|---|---|---|---|---|
Subjects: | Q Science > QB Astronomy Q Science > QC Physics |
|||||||||
Divisions: | Faculty of Science, Engineering and Medicine > Science > Physics | |||||||||
Library of Congress Subject Headings (LCSH): | Sun -- Loop prominences, Magnetohydrodynamics | |||||||||
Journal or Publication Title: | Astronomy & Astrophysics | |||||||||
Publisher: | EDP Sciences | |||||||||
ISSN: | 0004-6361 | |||||||||
Official Date: | 30 June 2017 | |||||||||
Dates: |
|
|||||||||
Volume: | 602 | |||||||||
Article Number: | A23 | |||||||||
DOI: | 10.1051/0004-6361/201629912 | |||||||||
Status: | Peer Reviewed | |||||||||
Publication Status: | Published | |||||||||
Access rights to Published version: | Open Access (Creative Commons) | |||||||||
Date of first compliant deposit: | 5 April 2017 | |||||||||
Date of first compliant Open Access: | 10 April 2017 | |||||||||
RIOXX Funder/Project Grant: |
|
Request changes or add full text files to a record
Repository staff actions (login required)
View Item |
Downloads
Downloads per month over past year