Zsámberger, N.K. and Erdélyi, R. (2022) Solar magneto-seismology of a magnetic slab in an asymmetric magnetic environment. The Astrophysical Journal, 934 (2). 155. ISSN 0004-637X
Abstract
Diagnosing the solar atmospheric plasma remains one of the major challenges in solar physics. In recent years, new methods have been developed to apply the powerful concept of solar magneto-seismology (SMS) to obtain information about plasma parameters in solar structures guiding magnetohydrodynamic (MHD) waves that would otherwise be difficult to measure. This paper uses the Cartesian model of a magnetic slab placed in an asymmetric magnetic environment to generalize recently discovered SMS techniques. Utilizing the fact that the asymmetric environment changes the character of the classical kink and sausage eigenmodes, we describe two spatial seismology methods built upon this mixed character of quasi-sausage and quasi-kink modes. First, we present the amplitude ratio technique, which compares the oscillation amplitudes measured at the two boundaries of the slab, and we provide expressions to estimate the internal Alfvén speed in the thin slab and in the incompressible plasma approximations. The second main technique relies on the changed distribution of wave power throughout the slab under the effect of waveguide asymmetry. This minimum perturbation shift technique is then also utilized to provide Alfvén speed estimates that depend on the plasma and magnetic parameters of the environment, as well as the measured slab width and oscillation frequency. Finally, we perform a brief investigation of how the amplitude ratio and the minimum perturbation shift depend on the different sources of waveguide asymmetry, and illustrate our findings with numerical results.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2022 The Authors. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence ( (https://creativecommons.org/licenses/by/4.0/). Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. |
Keywords: | Solar physics; The Sun; Magnetohydrodynamics; Solar atmosphere; Solar coronal seismology; Solar coronal waves |
Dates: |
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Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Science (Sheffield) > School of Mathematics and Statistics (Sheffield) |
Funding Information: | Funder Grant number SCIENCE AND TECHNOLOGY FACILITIES COUNCIL ST/M000826/1 |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 13 Oct 2022 11:20 |
Last Modified: | 13 Oct 2022 11:20 |
Status: | Published |
Publisher: | American Astronomical Society |
Refereed: | Yes |
Identification Number: | 10.3847/1538-4357/ac7be3 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:191429 |