Andrew Hillier (Exeter): 'Observations of MHD Turbulence in Solar Prominences'
Turbulence is believed to be a key dynamical process in in many astrophysical systems, playing a key role in many different aspects of solar activity from the dynamo to magnetic reconnection. The motions of plasma in quiescent prominences, as revealed by Hinode observations, display highly complex flows across a wide range of spatial and temporal scales, and with the small diffusivity and viscosity of the system, it is no surprise that prominences host turbulence. In this talk I will present my analysis of Hinode SOT dopplergrams of a quiescent prominence observed on the 2008-09-27. By investigating the spatial and temporal correlations between the line-of-sight velocity fluctuations, it was possible to determine the scaling of the power laws up to high-order in the velocity difference, which display powers that are at some scales consistent with weak MHD turbulence, and at others is consistent with strong MHD turbulence. I will present some interpretation of these results based on the current theoretical understanding of turbulence, but also highlight areas in which they do not match with theory, and hopefully provide satisfactory explanations as to why this is the case. These results present another piece of the puzzle that is understanding the complex nature of quiescent prominences, and also on the role how turbulence plays in the complex magnetic field found in the solar atmosphere.