Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Expansion of a plasma cloud into the solar wind   Three-dimensional (3D) hybrid particle-in-cell (PIC) simulations, with
kinetic ions and fluid electrons, of a plasma cloud expansion in the solar wind
are presented, revealing the dynamics of the expansion, with shock formation,
magnetic field compression, and the solar wind ions deflection around the
plasma bubble. The similarities of this system with a magnetosphere are also
pointed out.

31
The categories of this paper are: ao-sci
13
The categories of this paper are: quant-ph
17
The categories of this paper are: q-fin
25
The categories of this paper are: patt-sol
8
The categories of this paper are: hep-ex
30
The categories of this paper are: q-alg
18
The categories of this paper are: econ
20
The categories of this paper are: acc-phys
5
The categories of this paper are: gr-qc
24
The categories of this paper are: dg-ga
27
The categories of this paper are: comp-gas
12
The categories of this paper are: nucl-th
9
The categories of this paper are: nlin
7
The categories of this paper are: hep-th
28
The categories of this paper are: alg-geom
4
The categories of this paper are: cond-mat