Hierarchical analysis of the quiet-Sun magnetism

Asensio Ramos, A.; Martínez González, M. J.
Bibliographical reference

Astronomy and Astrophysics, Volume 572, id.A98, 8 pp.

Advertised on:
12
2014
Number of authors
2
IAC number of authors
2
Citations
19
Refereed citations
15
Description
Standard statistical analysis of the magnetic properties of the quiet Sun rely on simple histograms of quantities inferred from maximum-likelihood estimations. Because of the inherent degeneracies, either intrinsic or induced by the noise, this approach is not optimal and can lead to highly biased results. We carried out a meta-analysis of the magnetism of the quiet Sun from Hinode observations using a hierarchical probabilistic method. This method allowed us to infer the statistical properties of the magnetic field vector over the observed field-of-view, consistently taking into account the uncertainties in each pixel that are due to noise and degeneracies. Our results imply that the magnetic fields are very weak, below 275 G with 95% probability, with a slight preference for horizontal fields, although the distribution is not far from a quasi-isotropic distribution.
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