Astronomy and Astrophysics – Astrophysics
Scientific paper
Dec 1998
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1998a%26a...340..287n&link_type=abstract
Astronomy and Astrophysics, v.340, p.287-299 (1998)
Astronomy and Astrophysics
Astrophysics
3
Mhd, Waves, Sun: Chromosphere, Sun: Corona, Sun: Oscillations
Scientific paper
We study the steady state of nonlinear, small-amplitude, quasiresonant Alfven oscillations in a homogeneous dissipative hydromagnetic cavity which is forced by the shear motion of its boundaries. It is shown that, even in the case of strong nonlinearity, these oscillations can be represented, to leading order, by a sum of two solutions in the form of oppositely propagating waves with permanent shapes. An infinite set of nonlinear equations for the Fourier coefficients of these solutions is derived which, in general, admits multiple solutions, depending on the re-scaled total Reynolds number, R, and mistuning, Delta , between the frequency of the boundary forcing and the first Alfven eigenmode of the cavity. Two types of solutions are found. On the one hand, low-modal solutions set in over the entire parameter range studied, which can be represented, with a remarkable accuracy, by very few Fourier modes even at very large R. For a fixed Delta the time-averaged energy, {cal E}, that can be stored in the cavity is saturated, as R increases, to a value which is approximately proportional to epsilon (2) , epsilon (3) << 1 being the Alfven Mach number of the boundary motions. The time-averaged absorbed power (the Poynting flux {cal S}) scales as 1/R. For suitable values of R and Delta catastrophic transitions occur between these solutions, in which the average power released scales as R, provided R
Nocera Luigi
Ruderman Michael S.
No associations
LandOfFree
On the steady state of nonlinear quasiresonant Alfven oscillations in one-dimensional magnetic cavity 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 On the steady state of nonlinear quasiresonant Alfven oscillations in one-dimensional magnetic cavity, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and On the steady state of nonlinear quasiresonant Alfven oscillations in one-dimensional magnetic cavity will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-991855