题目：Thoughts on solving the solar heating problem…
报告人：Robertus Erdelyi, SP2RC, Sheffield University
时间：2016年8月12日 早上10:00
地点：闻天楼南楼211
Normal07.8 磅02falsefalsefalseEN-USZH-CNX-NONEMicrosoftInternetExplorer4Normal07.8 磅02falsefalsefalseEN-USZH-CNX-NONEMicrosoftInternetExplorer4Normal07.8 磅02falsefalsefalseEN-USZH-CNX-NONEMicrosoftInternetExplorer4MicrosoftInternetExplorer402DocumentNotSpecified7.8 磅Normal0MicrosoftInternetExplorer402DocumentNotSpecified7.8 磅Normal0MicrosoftInternetExplorer402DocumentNotSpecified7.8 磅Normal0Satellite (e.g. SOHO, TRACE, STEREO, Hinode, SDO and IRIS) and ground-based (e.g. DST/ROSA, IBIS, CoMP, SST/CRISP) observations have provided a wealth of evidence of waves and oscillations present in a wide range of spatial, temporal and spectral scales of the magnetised solar atmosphere. Our understanding about *localised* solar structures has been considerably changed in light of these high-resolution superb observations. However, these observations have also opened up further challenges. It is not anymore a question of what is the energy reservoir for solar pasta heating; not even how non-thermal energy can propagate from the reservoir to the place where it is dissipated. It is more the question of how the energy is transferred to heating. In order to shed light on this fundamental question, investigating MHD waves seem to be a way to proceed. MHD waves not only enable us to perform sub-resolution solar magneto-seismology (SMS) of waveguides but are also potential candidates to carry and *damp* the necessary non-thermal energy in these localised waveguides.
First, we briefly outline the basic recent developments in MHD wave theory relevant to solar plasma heating focussing on linear waves. Next, we 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, how these waves penetrate into the chromosphere, transition region or even into the low corona will be addressed.
Last, the latest reported observational findings of potential plentiful MHD wave flux, in terms of localised plasma heating, in the solar atmosphere with some surprising results will be discussed, bringing us closer to advance the coronal heating problem.
Prof Robertus Erdelyi:
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.
