Jain, R., Hindman, B.W., Braun, D.C. and Birch, A.C. (2009) Absorption of p-modes by thin magnetic flux tubes. Astrophysical Journal, 695 (1). pp. 325-335.
We study the interaction between p modes and the many magnetic fibrils that lace the solar convection zone. In particular, we investigate the resulting absorption of p-mode energy by the fibril magnetic field. Through mechanical buffeting, the p modes excite tube waves on the magnetic fibrils—in the form of longitudinal sausage waves and transverse kink waves. The tube waves propagate up and down the magnetic fibrils and out of the p-mode cavity, thereby removing energy from the incident acoustic waves. We compute the absorption coefficient associated with this damping mechanism and model the absorption that would be observed for magnetic plage. We compare our results to the absorption coefficient that is measured using the local-helioseismic technique of ridge-filtered holography. We find that, depending on the mode order and the photospheric boundary conditions, we can achieve absorption coefficients for simulated plage that exceed 50%. The observed increase of the absorption coefficient as a function of frequency is reproduced for all model parameters.
|Institution:||The University of Sheffield|
|Academic Units:||The University of Sheffield > Faculty of Science (Sheffield) > School of Mathematics and Statistics (Sheffield)|
|Depositing User:||Mrs Megan Hobbs|
|Date Deposited:||09 Mar 2010 16:10|
|Last Modified:||16 Nov 2015 11:48|
|Publisher:||Institute of Physics|