Nonlinear Magnetohydrodynamic Evolution of Line-tied Coronal Loops

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

49

Magnetohydrodynamics: Mhd, Sun: Corona, Sun: Magnetic Fields

Scientific paper

Simulations of the nonlinear evolution of the m = 1 kink mode in magnetic flux tubes with line-tying boundary conditions are presented. The initial structure of the flux tube is intended to model a solar coronal loop that either has evolved quasi-statically through sequences of equilibria with increasing twist due to the application of localized photospheric vortex flows or has emerged with a net current through the photosphere. It is well known that when the twist exceeds a critical value that depends on its radial profile and on the loop length, the loop becomes kink unstable. The nonlinear evolution of the instability is followed using a three-dimensional MHD code in cylindrical geometry, in different types of magnetic field configurations, with the common property that the current is confined within the same radius, so that the magnetic field is potential in the external regions. The differences reside in the net axial current carried by the structure, ranging from a vanishing current (corresponding to an outer axial potential field) to a high current (corresponding to an outer almost azimuthal potential field). It is shown that, during the nonlinear phase of the instability, loops develop current sheets and, consequently, their evolution becomes resistive with the occurrence of magnetic reconnection. The dependence of the topology of the currents at saturation on the initial magnetic structure, the details of the reconnection phenomenon, and the resistive dissipation mechanism are examined. Finally, the impact of the results on the understanding of coronal activity is discussed.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Nonlinear Magnetohydrodynamic Evolution of Line-tied Coronal Loops does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Nonlinear Magnetohydrodynamic Evolution of Line-tied Coronal Loops, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Nonlinear Magnetohydrodynamic Evolution of Line-tied Coronal Loops will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1223414

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.