Transverse oscillations of coronal loops
Lead Research Organisation:
University of Sheffield
Department Name: Applied Mathematics
Abstract
It has been known for a few decades that the solar atmosphere is strongly magnetically structured. One of the main magnetic structures are the coronal loops. These loops are the structures elongated in the magnetic field direction in the solar corona that are characterized by the enhanced density and temperature of the plasma. In 1998 TRACE observed first oscillations of these structures in the transverse direction caused by an external perturbation (most probably generated by a solar flare). After that the phenomenon of transverse coronal loop oscillations received an ample attention of solar physicists. Transverse oscillations are especially important because they are the key objects of studies in the new and fast emerging branch of solar physics called coronal seismology or solar magneto-seismology. The main idea of coronal seismology is to obtain information about parameters of the coronal plasma and magnetic field from observations of waves and oscillations taking place in the solar corona. The transverse coronal loop oscillations have been used to estimate: (i) The magnetic field magnitude in coronal loops; (ii) The atmospheric scale height in the solar corona. To achieve sufficient accuracy in the estimates of this type a well-developed theory of transverse coronal loop oscillations is much needed. The main goal of this theory is to separate coronal loop parameters that are important in seismological applications from those that are not important, and thus can be neglected. Initial but vital progress has already been made in this direction in the recent years. For example, it has been shown that the variation of the density and cross-section radius along the loop are very important, while loop curvature and the magnetic twist are less important at the level of present and near-future instrumental resolution. However, the theory of transverse coronal loop oscillations is far from being complete. New and more sophisticated models are to be developed in order to obtain sub-resolution diagnostic informations. Among the main theoretical challenges are the development of nonlinear theory of transverse coronal loop oscillations, and the theory of collective oscillations of a system of a few coronal loops. Our project addresses these crucial advanced problems.
Publications
Andries J
(2009)
Coronal Seismology by Means of Kink Oscillation Overtones
in Space Science Reviews
Kuridze D
(2013)
CHARACTERISTICS OF TRANSVERSE WAVES IN CHROMOSPHERIC MOTTLES
in The Astrophysical Journal
Morton R
(2011)
Torsional Alfvén waves: magneto-seismology in static and dynamic coronal plasmas
in Astronomy & Astrophysics
Morton R
(2014)
THE GENERATION AND DAMPING OF PROPAGATING MHD KINK WAVES IN THE SOLAR ATMOSPHERE
in The Astrophysical Journal
Morton R
(2011)
Kink and fluting modes of stratified coronal magnetic loops with elliptical cross-sections
in Astronomy & Astrophysics
Morton R
(2010)
Application of the theory of damping of kink oscillations by radiative cooling of coronal loop plasma
in Astronomy and Astrophysics
Robertson D
(2010)
Resonantly damped oscillations of two coronal loops
in Astronomy & Astrophysics
Robertson D
(2010)
The effect of density stratification on the transverse oscillations of two parallel coronal loops
in Astronomy and Astrophysics
Ruderman M
(2009)
Transverse Oscillations of Coronal Loops
in Space Science Reviews
Ruderman M
(2011)
Resonant damping of kink oscillations of cooling coronal magnetic loops
in Astronomy & Astrophysics
Description | We managed to substantially develop the theory of kink oscillations of magnetic flux tubes. This theory is used in coronal seismology that enables us to get important information about conditions in the solar atmosphere. |
Exploitation Route | The results obtained in the research funded by the award are used by other research, in particular, in coronal seismology. |
Sectors | Aerospace, Defence and Marine,Environment |
Description | KULeuven_Belgium |
Organisation | University of Leuven |
Department | Department of Mathematics |
Country | Belgium |
Sector | Academic/University |
PI Contribution | I provided the analytical study of nonlinear kink wave propagation in magnetic flux tubes |
Collaborator Contribution | They carried out the numerical study of nonlinear kink wave propagation in magnetic flux tubes |
Impact | We studied the nonlinearity effect on the kink wave propagation in magnetic flux tubes |
Start Year | 2009 |
Description | St_Andrews |
Organisation | University of St Andrews |
Department | Department of Mathematics and Statistics |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | We provided the theoretical consideration of damping of kink oscillations due to resonant absorption. |
Collaborator Contribution | They actively participate in the discussions on resonant absorption. |
Impact | We managed to study the resonant damping of kink oscillations in a system of two parallel magnetic tubes |
Start Year | 2009 |