Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Evolution of three-dimensional coherent structures in Hall
  magnetohydrodynamics   The work extends the computational model EULAG-MHD to include Hall
magnetohydrodynamics (HMHD)---important to explore physical systems undergoing
fast magnetic reconnection at the order of the ion inertial length scale.
Examples include solar transients along with reconnections in magnetosphere,
magnetotail and
  laboratory plasmas. The paper documents the results of two distinct sets of
implicit large-eddy simulations in the presence and absence of the Hall forcing
term, initiated with an unidirectional sinusoidal magnetic field. The HMHD
simulation while benchmarking the code also emphasizes the complexity of three
dimensional (3D) evolution over its two dimensional (2D) counterpart. The
magnetic reconnections onset significantly earlier in HMHD. Importantly, the
magnetic field generated by the Hall term breaks any inherent symmetry,
ultimately making the evolution 3D. The resulting 3D reconnections develop
magnetic flux ropes and magnetic flux tubes. Projected on the reconnection
plane, the ropes and tubes appear as magnetic islands, which later break into
secondary islands, and finally coalesce to generate an X-type neutral point.
These findings are in agreement with the theory and contemporary simulations of
HMHD, and thus verify our extension of the EULAG-MHD model. The second set
explores the influence of the Hall forcing on generation and ascend of a
magnetic flux rope from sheared magnetic arcades---a novel scenario instructive
in understanding the coronal transients. The rope evolves through intermediate
complex structures, ultimately breaking locally because of reconnections.
Interestingly, the breakage occurs earlier in the presence of the Hall term,
signifying faster dynamics leading to magnetic topology favorable for
reconnections.

13
The categories of this paper are: quant-ph
33
The categories of this paper are: plasm-ph
28
The categories of this paper are: alg-geom
12
The categories of this paper are: nucl-th
22
The categories of this paper are: chao-dyn
21
The categories of this paper are: adap-org
11
The categories of this paper are: hep-lat
2
The categories of this paper are: math
8
The categories of this paper are: hep-ex
3
The categories of this paper are: physics
37
The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph
1
The categories of this paper are: cs
25
The categories of this paper are: patt-sol
0
The categories of this paper are: hep-ph
29
The categories of this paper are: funct-an