Numerical simulations of vertical oscillations of a multi-stranded coronal loop

¹ Group of Astrophysics and Gravity Theory, Institute of Physics, UMCS, ul. Radziszewskiego 10, 20-031 Lublin, Poland e-mail: marcingruszecki@wp.pl
² The Catholic University of America, NASA Goddard Space Flight Center, Code 612.1, Greenbelt, MD 20771, USA

Received: 12 April 2006
Accepted: 5 September 2006

Abstract

Aims. We consider impulsively generated oscillations in a 2D model of a curved solar coronal arcade loop that consists of up to 5 strands of dense plasma.

Methods. First we do a simulation for a loop which consists of two curved strands. We evaluate by means of numerical simulations the influence of the distance between the strands and their number on wave period, attenuation time, and amplitudes of standing kink waves.

Results. The results of the numerical simulations reveal that only strands which are very close to each other (distance comparable to the strand width) considerably change the collective behavior of kink oscillations. More distant strands also exhibit weak coupling of the oscillations. However, their behavior can essentially be explained in terms of separate oscillating loops. We compare the numerical results with recent TRACE observational findings, and find qualitative agreement.