Magnetic loops in the quiet Sun
Abstract
We investigate the fine structure of magnetic fields in the atmosphere of the quiet Sun. We use photospheric magnetic field measurements from {\sc Sunrise}/IMaX with unprecedented spatial resolution to extrapolate the photospheric magnetic field into higher layers of the solar atmosphere with the help of potential and force-free extrapolation techniques. We find that most magnetic loops which reach into the chromosphere or higher have one foot point in relatively strong magnetic field regions in the photosphere. of the magnetic energy in the mid chromosphere (at a height of 1 Mm) is in field lines, whose stronger foot point has a strength of more than 300 G, i.e. above the equipartition field strength with convection. The loops reaching into the chromosphere and corona are also found to be asymmetric in the sense that the weaker foot point has a strength G and is located in the internetwork. Such loops are expected to be strongly dynamic and have short lifetimes, as dictated by the properties of the internetwork fields.
Cite
@article{arxiv.1009.4715,
title = {Magnetic loops in the quiet Sun},
author = {Thomas Wiegelmann and Sami K Solanki and Juan Borrero and Valentin Martinez Pillet and J. C. del Toro Iniesta and Vicente Domingo and J. A. Bonet Navarro and Peter Barthol and Achim Gandorfer and Michael Knoelker and Wolfgang Schmidt and Alan M. Title},
journal= {arXiv preprint arXiv:1009.4715},
year = {2015}
}
Comments
accepted for ApJL Sunrise special issue, 8 Pages, 4 Figures