Magnetoacoustic Waves in Sunspots

Bibcode
2003ApJ...588..606K
DOI
10.1086/373918
Khomenko, E. V.; Collados, M.; Bellot Rubio, L. R.
Bibliographical reference

The Astrophysical Journal, Volume 588, Issue 1, pp. 606-619.

Advertised on:
5
2003
Journal
The Astrophysical Journal
Number of authors
3
IAC number of authors
1
Citations
37
Refereed citations
33
Description
Observed variations of the magnetic field strength in sunspot umbrae consist of intrinsic oscillations and ``false'' oscillations due to time-dependent opacity effects. Here we present an approach intended for the separation of these components. We develop a mathematical formalism based on the analytical solution of the MHD equations including gravity, inclination of the magnetic field, and effects of nonadiabaticity. The theoretical results are compared with observations in the near-infrared at 1.56 μm by Bellot Rubio and coworkers using the Tenerife Infrared Polarimeter. It is shown that part of the detected field strength variations can be intrinsic magnetic field oscillations caused by magnetoacoustic waves.
Type
Refereed
Sunspots

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