MacTaggart, D. , Guglielmino, S. L. and Zuccarello, F. (2016) The pre-penumbral magnetic canopy in the solar atmosphere. Astrophysical Journal Letters, 831(1), L4. (doi: 10.3847/2041-8205/831/1/L4)
|
Text
130317.pdf - Accepted Version 776kB |
Abstract
Penumbrae are the manifestation of magnetoconvection in highly inclined (to the vertical direction) magnetic field. The penumbra of a sunspot tends to form, initially, along the arc of the umbra antipodal to the main region of flux emergence. The question of how highly inclined magnetic field can concentrate along the antipodal curves of umbrae, at least initially, remains to be answered. Previous observational studies have suggested the existence of some form of overlying magnetic canopy which acts as the progenitor for penumbrae. We propose that such overlying magnetic canopies are a consequence of how the magnetic field emerges into the atmosphere and are, therefore, part of the emerging region. We show, through simulations of twisted flux tube emergence, that canopies of highly inclined magnetic field form preferentially at the required locations above the photosphere.
Item Type: | Articles |
---|---|
Status: | Published |
Refereed: | Yes |
Glasgow Author(s) Enlighten ID: | Mactaggart, Dr David |
Authors: | MacTaggart, D., Guglielmino, S. L., and Zuccarello, F. |
College/School: | College of Science and Engineering > School of Mathematics and Statistics > Mathematics |
Journal Name: | Astrophysical Journal Letters |
Publisher: | IOP Publishing |
ISSN: | 2041-8205 |
ISSN (Online): | 2041-8213 |
Published Online: | 24 October 2016 |
Copyright Holders: | Copyright © 2016 The American Astronomical Society |
First Published: | First published in Astrophysical Journal Letters 831(1):L4 |
Publisher Policy: | Reproduced in accordance with the copyright policy of the publisher |
Related URLs: |
University Staff: Request a correction | Enlighten Editors: Update this record