Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Neutralization of ion beam by electron injection, Part 2: Excitation and
  propagation of electrostatic solitary waves   The charge neutralization of an ion beam by electron injection is
investigated using a two-dimensional electrostatic particle-in-cell code. The
simulation results show that electrostatic solitary waves (ESWs) can be
robustly generated in the neutralization process and last for long time (for
more than 30 us); and therefore ESW can strongly affect the neutralization
process. The ESWs propagate along the axis of the ion beam and reflect from the
beam boundaries. The simulations clearly show that two ESWs can pass through
each other with only small changes in amplitude. Partial exchange of trapped
electrons in collisions of two ESWs is observed in the simulations and can
explain interaction during collisions of two ESWs. Coalescence of two ESWs is
also observed.

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The categories of this paper are: cond-mat
33
The categories of this paper are: plasm-ph
28
The categories of this paper are: alg-geom
19
The categories of this paper are: eess
34
The categories of this paper are: chem-ph
11
The categories of this paper are: hep-lat
27
The categories of this paper are: comp-gas
12
The categories of this paper are: nucl-th
30
The categories of this paper are: q-alg
32
The categories of this paper are: atom-ph
13
The categories of this paper are: quant-ph
18
The categories of this paper are: econ
21
The categories of this paper are: adap-org
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The categories of this paper are: hep-ph
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The categories of this paper are: hep-ex
24
The categories of this paper are: dg-ga