@article{Cargill:2016:1/31,
author = {Cargill, PJ and DeMoortel, I and Kiddie, G},
doi = {1/31},
journal = {Astrophysical Journal},
title = {Coronal density structure and its role in wave damping in loops},
url = {http://dx.doi.org/10.3847/0004-637X/823/1/31},
volume = {823},
year = {2016}
}

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TY  - JOUR
AB  - It has long been established that gradients in the Alfvén speed, and in particular the plasmadensity, are an essential part of the damping of waves in the magnetically closed solar coronaby mechanisms such as resonant absorption or phase mixing. While models of wave dampingoften assume a fixed density gradient, in this paper the self-consistency of such calculationsis assessed by examining the temporal evolution of the coronal density. It is shownconceptually that for some coronal structures, density gradients can evolve in a way that thewave damping processes are inhibited. For the case of phase mixing we argue that: (a) waveheating cannot sustain the assumed density structure and (b) inclusion of feedback of theheating on the density gradient can lead to a highly structured density, although on longtimescales. In addition, transport coefficients well in excess of classical are required tomaintain the observed coronal density. Hence, the heating of closed coronal structures byglobal oscillations may face problems arising from the assumption of a fixed density gradientand the rapid damping of oscillations may have to be accompanied by a separate (non-wavebased) heating mechanism to sustain the required density structuring.
AU  - Cargill,PJ
AU  - DeMoortel,I
AU  - Kiddie,G
DO  - 1/31
PY  - 2016///
SN  - 1538-4357
TI  - Coronal density structure and its role in wave damping in loops
T2  - Astrophysical Journal
UR  - http://dx.doi.org/10.3847/0004-637X/823/1/31
UR  - http://hdl.handle.net/10044/1/30938
VL  - 823
ER  - 

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