科研之友
微信
新浪微博
Facebook
分享链接
摘要
A new magnetohydrodynamic (MHD) instability in coronal loops is presented. It is demonstrated that small-amplitude torsional Alfvenic disturbances generated by random photospheric motions are inevitably amplified in asymmetrically stratified loops with siphon flows. The loop asymmetry and the flow speeds can be arbitrarily small. The growth rates linked with the instability increase with increasing flow speeds. The instability is caused by over-reflection of Alfven waves at the transition region where steep variations in density exist.
- 出版日期2009-3-20
