Analysis of spatially deconvolved polar faculae

Quintero Noda, C.; Suematsu, Y.; Ruiz Cobo, B.; Shimizu, T.; Asensio Ramos, A.
Bibliographical reference

Monthly Notices of the Royal Astronomical Society, Volume 460, Issue 1, p.956-965

Advertised on:
7
2016
Number of authors
5
IAC number of authors
2
Citations
9
Refereed citations
9
Description
Polar faculae are bright features that can be detected in solar limb observations and they are related to magnetic field concentrations. Although there are a large number of works studying them, some questions about their nature as their magnetic properties at different heights are still open. Thus, we aim to improve the understanding of solar polar faculae. In that sense, we infer the vertical stratification of the temperature, gas pressure, line-of-sight velocity and magnetic field vector of polar faculae regions. We performed inversions of the Stokes profiles observed with Hinode/Spectropolarimeter after removing the stray light contamination produced by the spatial point spread function of the telescope. Moreover, after solving the azimuth ambiguity, we transform the magnetic field vector to local solar coordinates. The obtained results reveal that the polar faculae are constituted by hot plasma with low line-of-sight velocities and single polarity magnetic fields in the kilogauss range that are nearly perpendicular to the solar surface. We also found that the spatial location of these magnetic fields is slightly shifted respect to the continuum observations towards the disc centre. We believe that this is due to the hot wall effect that allows detecting photons that come from deeper layers located closer to the solar limb.