Coronal energy release by MHD avalanches: continuous driving
Abstract
Previous work has confirmed the concept of a magnetohydrodynamic (MHD) avalanche in pre-stressed threads within a coronal loop. We undertook a series of full, three-dimensional MHD simulations in order to create three threads by twisting the magnetic field through boundary motions until an instability ensues. We find that, following the original instability, one unstable thread can disrupt its neighbours with continued driving. A "bursty" heating profile results, with a series of ongoing energy releases, but no evident steady state. For the first time using full MHD, we show that avalanches are a viable mechanism for the storing and release of magnetic energy in the solar corona, as a result of photospheric motions.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- July 2018
- DOI:
- 10.1051/0004-6361/201732399
- Bibcode:
- 2018A&A...615A..84R
- Keywords:
-
- Sun: corona;
- Sun: magnetic fields;
- magnetohydrodynamics (MHD);
- methods: numerical