Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nonlinear excitation of fine-radial-scale zonal structures by toroidal
  Alfven eigenmode   The set of equations describing nonlinear evolution of a single toroidal
Alfven eigenmode are derived, including both zero frequency zonal structure
(ZFZS) generation and wave-particle phase space nonlinearities. The simplified
case of neglecting wave-particle phase space nonlinearity is then investigated
to focus on different roles of energetic particles and bulk plasmas on ZFZS
generation. It is shown that energetic particles and bulk plasma play dominant
roles in ZFZS generation in different nonlinear stages, and the corresponding
processes are qualitatively different. Several properties of ZFZS generation,
e.g., fine- vs. meso-scale, forced driven vs. spontaneous excitation, are
clarified by the present analysis.

11
The categories of this paper are: hep-lat
22
The categories of this paper are: chao-dyn
37
The categories of this paper are: supr-con
36
The categories of this paper are: cmp-lg
28
The categories of this paper are: alg-geom
21
The categories of this paper are: adap-org
9
The categories of this paper are: nlin
18
The categories of this paper are: econ
19
The categories of this paper are: eess
5
The categories of this paper are: gr-qc
33
The categories of this paper are: plasm-ph
0
The categories of this paper are: hep-ph
20
The categories of this paper are: acc-phys
31
The categories of this paper are: ao-sci
12
The categories of this paper are: nucl-th
8
The categories of this paper are: hep-ex