Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Parametric decay of plasma waves near the upper-hybrid resonance   An intense X wave propagating perpendicularly to dc magnetic field is
unstable with respect to a parametric decay into an electron Bernstein wave and
a lower-hybrid wave. A modified theory of this effect is proposed that extends
to the high-intensity regime, where the instability rate $\gamma$ ceases to be
a linear function of the incident-wave amplitude. An explicit formula for
$\gamma$ is derived and expressed in terms of cold-plasma parameters. Theory
predictions are in reasonable agreement with the results of the
particle-in-cell simulations presented in a separate publication.

34
The categories of this paper are: chem-ph
36
The categories of this paper are: cmp-lg
13
The categories of this paper are: quant-ph
2
The categories of this paper are: math
31
The categories of this paper are: ao-sci
28
The categories of this paper are: alg-geom
22
The categories of this paper are: chao-dyn
6
The categories of this paper are: astro-ph
24
The categories of this paper are: dg-ga
15
The categories of this paper are: nucl-ex
30
The categories of this paper are: q-alg
26
The categories of this paper are: bayes-an
21
The categories of this paper are: adap-org
10
The categories of this paper are: q-bio
18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex