Seminar:
Title: MHD wave heating of localised solar magnetic structures: Does it work?
Speaker: Prof Róbert von Fáy-Siebenbürgen
Time： 16:00, 27 October (tomorrow)
Location：Room 208 (south building)
Abstract:
Satellite and ground-based observations from e.g. SOHO, TRACE, STEREO, Hinode, SDO and IRIS to DST/ROSA, IBIS, CoMP, STT/CRISP have provided a wealth of evidence of waves and oscillations present in a wide range of spatial scales of the magnetised solar atmosphere. Our understanding about localised solar structures has been considerably changed in light of these high spatial and time resolution observations. However, MHD waves not only enable us to perform sub-resolution magneto-seismology of magnetic waveguides but are also potential candidates to carry and damp the necessary non-thermal energy in these localised waveguides. First, we will briefly outline the basic recent developments in MHD wave theory focussing on linear waves.
Next, we will concentrate on the role of the most frequently studied wave classes, including the Alfven, and magneto-acoustic kink and sausage waves. The current theoretical (and often difficult) interpretations of the detected solar atmospheric wave and oscillatory phenomena within the framework of MHD will be shown. Their photospheric origin and generation mechanism and how these waves penetrate into the chromosphere, transition region or even into the corona will be addressed.
Last, the latest reported observational findings of potential MHD wave flux, in terms of localised plasma heating, in the solar atmosphere with some surprising results will be discussed, bringing us closer to solve the coronal heating problem.
Prof Róbert von Fáy-Siebenbürgen：
His main research interests lie in the general field of space plasma physics. The heating processes that generate and sustain the observed high temperature of the solar and stellar atmospheres have so far defied a quantitative understanding despite the multitude of efforts spanning over half a century. The aim of his research is to address these questions through theoretical (both numerical and exact analytical methods) and observational studies (joint ground-based and satellite missions). Particular attention is paid to the solar influence on the magnetosphere and space weather.
Understanding the subtleties of plasma confinement at high temperatures is also strongly linked to modern fusion physics. His interdisciplinary research (including e.g. magnetohydrodynamics [MHD], computational fluid dynamics [CFD], kinetic theory) has direct applications in the new and rapidly emerging discipline of helioseismology and space weather. He became Head of the Solar Physics & Upper-Atmosphere Research Group (SPARG) in the Department of Applied Mathematics in 2004.
