Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Three-dimensional simulations of ion dynamics in the plasma of an
  Electron Cyclotron Resonance Ion Source
22
The categories of this paper are: chao-dyn
18
The categories of this paper are: econ
16
The categories of this paper are: stat
14
The categories of this paper are: math-ph
32
The categories of this paper are: atom-ph
35
The categories of this paper are: mtrl-th
19
The categories of this paper are: eess
30
The categories of this paper are: q-alg
8
The categories of this paper are: hep-ex
2
The categories of this paper are: math
9
The categories of this paper are: nlin
13
The categories of this paper are: quant-ph
4
The categories of this paper are: cond-mat
27
The categories of this paper are: comp-gas
17
The categories of this paper are: q-fin
23
The categories of this paper are: solv-int