The effects of twisted magnetic field on coronal loops oscillations and dissipation
نویسندگان
چکیده
The standing MHD modes in a zero-β cylindrical magnetic flux tube modelled as a straight core surrounded by a magnetically twisted annulus, both embedded in a straight ambient external field is considered. The dispersion relation for the fast MHD waves is derived and solved numerically to obtain the frequencies of both the kink (m = 1), and fluting (m = 2, 3) waves. Damping rates due to both viscous and resistive dissipations in presence of the twisted magnetic field is derived and solved numerically for both the kink and fluting waves.
منابع مشابه
برانگیختگی و میرایی نوسانات عرضی در حلقه‌های تاج توسط پدیده ویک
Transversal oscillation of coronal loops that are interpreted as signatures of magneto hydrodynamics (MHD) waves are observed frequently in active region corona loops. The amplitude of this oscillation has been found to be strongly attenuated. The damping of transverse oscillation may be produced by the dissipation mechanism and the wake of the traveling disturbance. The damping of transversal ...
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متن کاملزمان میرایی نوسانات عرضی کینک مشاهده شده در حلقه های تاج نواحی فعال با استفاده از تلسکوپ ای آی ای نصب شده بر اس دی او
A coronal loop can be oscillated in various directions. A basic type of coronal loop oscillation is called transverse oscillation that can be caused by different factors, such as nearby active regions and flares. The damping of transverse oscillation may be produced by the dissipation mechanism or the wake of the traveling disturbance. The aim of this paper is to estimate the damping time of tr...
متن کاملThe effects of twisted magnetic field on coronal loop oscillations and dissipation
The standing magnetohydrodynamic (MHD) modes in a cylindrical incompressible magnetic flux tube modelled as a straight core surrounded by a magnetically twisted annulus, both embedded in a straight ambient external field, are considered. The dispersion relation for the MHD waves is derived and solved numerically to obtain the frequencies of both the kink (m = 1) and fluting (m = 2, 3) waves. Da...
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