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arXiv · 1410.5953

Hierarchical analysis of the quiet Sun magnetism

A. Asensio Ramos·M. J. Martínez González
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Abstract

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 carry out a meta-analysis of the magnetism of the quiet Sun from Hinode observations using a hierarchical probabilistic method. This model allows 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 due to noise and degeneracies. Our results point out that the magnetic fields are very weak, below 275 G with 95% credibility, with a slight preference for horizontal fields, although the distribution is not far from a quasi-isotropic distribution.

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A. Asensio Ramos, M. J. Martínez González. 2014-10-22. Hierarchical analysis of the quiet Sun magnetism. https://doi.org/10.1051/0004-6361/201423860

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