Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Model for Spontaneous Onset of Fast Magnetic Reconnection   We present a model for the spontaneous onset of fast magnetic reconnection in
a weakly collisional plasma, such as the solar corona. When a current layer of
macroscopic width undergoes collisional (Sweet-Parker) reconnection, a narrow
dissipation region forms around the X-line. This dissipation region naturally
becomes narrower during the reconnection process as stronger magnetic fields
are convected toward the X-line. When the dissipation region becomes thinner
than the ion skin depth, resistive magnetohydrodynamics breaks down as the Hall
effect becomes important and the Sweet-Parker solution ceases to exist. A
transition to collisionless (Hall) reconnection ensues, increasing the
reconnection rate by many orders of magnitude in a very short time. Predictions
of the model are consistent with constraints set by observations of solar
flares.

30
The categories of this paper are: q-alg
0
The categories of this paper are: hep-ph
36
The categories of this paper are: cmp-lg
24
The categories of this paper are: dg-ga
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The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
14
The categories of this paper are: math-ph
10
The categories of this paper are: q-bio
15
The categories of this paper are: nucl-ex
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The categories of this paper are: alg-geom
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The categories of this paper are: patt-sol
18
The categories of this paper are: econ
20
The categories of this paper are: acc-phys
13
The categories of this paper are: quant-ph
11
The categories of this paper are: hep-lat
5
The categories of this paper are: gr-qc