Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Swing wave-wave interaction: Coupling between fast magnetosonic and
  Alfv{\'e}n waves   We suggest a mechanism of energy transformation from fast magnetosonic waves
propagating across a magnetic field to Alfv{\'e}n waves propagating along the
field. The mechanism is based on {\it swing wave-wave interaction} [T.V.
Zaqarashvili, Astrophys. J. Lett. {\bf 552}, 107 (2001)]. The standing fast
magnetosonic waves cause a periodical variation in the Alfv{\'e}n speed, with
the amplitude of an Alfv{\'e}n wave being governed by Mathieu's equation.
Consequently, sub-harmonics of Alfv{\'e}n waves with a frequency half that of
magnetosonic waves grow exponentially in time. It is suggested that the energy
of nonelectromagnetic forces, which are able to support the magnetosonic
oscillations, may be transmitted into the energy of purely magnetic
oscillations. Possible astrophysical applications of the mechanism are briefly
discussed.

16
The categories of this paper are: stat
0
The categories of this paper are: hep-ph
18
The categories of this paper are: econ
13
The categories of this paper are: quant-ph
28
The categories of this paper are: alg-geom
4
The categories of this paper are: cond-mat
36
The categories of this paper are: cmp-lg
22
The categories of this paper are: chao-dyn
19
The categories of this paper are: eess
20
The categories of this paper are: acc-phys
15
The categories of this paper are: nucl-ex
33
The categories of this paper are: plasm-ph
11
The categories of this paper are: hep-lat
34
The categories of this paper are: chem-ph
29
The categories of this paper are: funct-an
21
The categories of this paper are: adap-org