Vertical oscillations of an arcade loop in a gravitationally stratified solar corona
Group of Astrophysics and Gravity Theory, Institute of Physics, UMCS, ul. Radziszewskiego 10, 20-031 Lublin, Poland e-mail: email@example.com
Accepted: 9 May 2008
Aims. We consider impulsively-generated vertical oscillations of an arcade loop that is embedded in the gravitationally-stratified solar corona.
Methods. Two-dimensional magnetohydrodynamic equations are solved numerically in the limit of an ideal plasma.
Results. The numerical results indicate that the effect of gravity produces a decrease in the wave period and an increase in the attenuation time. This decrease is a consequence of a higher Alfvén speed within the gravitationally-stratified arcade loop, while the weaker attenuation reflects a smaller amount of wave tunneling than in the gravity-free case. These results are reminiscent of those for TRACE data.
Key words: magnetohydrodynamics (MHD) / Sun: corona / Sun: oscillations
© ESO, 2008