Bayesian magnetohydrodynamic seismology of coronal loops 

Inigo Arregui Submitted: 20110721 01:41
We perform a Bayesian parameter inference in the context of resonantly damped transverse coronal loop oscillations. The forward problem is solved in terms of parametric results for kink waves in onedimensional flux tubes in the thin tube and thin boundary approximations. For the inverse problem, we adopt a Bayesian approach to infer the most probable values of the relevant parameters, for given observed periods and damping times, and to extract their confidence levels. The posterior probability distribution functions are obtained by means of Markov Chain Monte Carlo simulations, incorporating observed uncertainties in a consistent manner. We find well localized solutions in the posterior probability distribution functions for two of the three parameters of interest, namely the Alfvén travel time and the transverse inhomogeneity lengthscale. The obtained estimates for the Alfvén travel time are consistent with previous inversion results, but the method enables us to additionally constrain the transverse inhomogeneity lengthscale and to estimate real error bars for each parameter. When observational estimates for the density contrast are used, the method enables us to fully constrain the three parameters of interest. These results can serve to improve our current estimates of unknown physical parameters in coronal loops and to test the assumed theoretical model.
Authors: Inigo Arregui, Andres Asensio Ramos
Projects: None

Publication Status: ApJ, accepted
Last Modified: 20110721 08:42


