Instabilities, nonlinearities and heating in the solar corona
Coronal Dynamics, Heating
The current generation of advanced solar observing facilities is beginning to reveal the nature of the corona in unprecedented detail. Whilst it is becoming increasingly clear that dynamic and complex behaviour is pervasive throughout the Sun’s atmosphere, many of the observed physical processes remain poorly understood. This session will explore magnetohydrodynamic (MHD) instabilities, wave-induced turbulence and the nature of the energy release which sustains the multi-million degree coronal temperatures.
Mechanisms proposed to explain coronal heating can be grouped according to the temporal behaviour of the underlying energy source. On one hand, long time scale flows will slowly build magnetic stress which can be released through reconnection events and on the other, short time scale flows will induce MHD waves which can dissipate in the corona. The relative importance of these two categories remains unclear and may well vary throughout the coronal volume. In either case, for significant energy release to occur, small length scales must be generated in either the magnetic or velocity fields (or both). A popular mechanism by which these small scales may arise is the formation of an energy cascade during the development of MHD turbulence. This may form as a result of the nonlinear interaction of counter-propagating wave modes, the disruption of unidirectionally propagating kink modes or due to dynamic and thermal instabilities such as the Kelvin-Helmholtz and Rayleigh-Taylor-type instabilities. All of these nonlinear phenomena must be explored in detail in order to fully understand the complex nature of the solar corona.
Schedule:
15:30 Munehito Shoda “Parametric decay instability of Alfvén wave and its role in the solar wind acceleration”
15:54 Cosima Breu “A solar coronal loop in a box: energy generation, heating and dynamics”
16:06 Jeffersson Agudelo “Energy distribution during 3D small scale magnetic reconnection in plasma turbulence”
16:18 Thomas Rees-Crockford “Matching Simulations and Observations of the Rayleigh-Taylor Instability in a Quiet-Sun Hedgerow Prominence.”
16:30 Lakshmi Pradeep Chitta “What drives the hot solar corona?”
16:54 Ramada Sukarmadji “Observations of nanojets in multi-structures and from different drivers: from KHI-driven reconnection in a blowout jet to coronal rain loops”
17:06 Dmitrii Kolotkov “Thermal stability of the Sun’s corona and the coronal heating function”
17:18 Raheem Beg “Self-generated turbulent reconnection in the 3D high-Rm solar corona”
Norbert Magyar, Thomas Howson, Patrick Antolin, Andrew Hillier, Jack Reid, Alan Hood, Craig Johnston
Wednesday afternoon
All attendees are expected to show respect and courtesy to other attendees and staff, and to adhere to the NAM Code of Conduct.