Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Magnetic Reconnection Onset via Disruption of a Forming Current Sheet by
  the Tearing Instability   The recent realization that Sweet-Parker current sheets are violently
unstable to the secondary tearing (plasmoid) instability implies that such
current sheets cannot occur in real systems. This suggests that, in order to
understand the onset of magnetic reconnection, one needs to consider the growth
of the tearing instability in a current layer as it is being formed. Such an
analysis is performed here in the context of nonlinear resistive MHD for a
generic time-dependent equilibrium representing a gradually forming current
sheet. It is shown that two onset regimes, single-island and multi-island, are
possible, depending on the rate of current sheet formation. A simple model is
used to compute the criterion for transition between these two regimes, as well
as the reconnection onset time and the current sheet parameters at that moment.
For typical solar corona parameters this model yields results consistent with
observations.

22
The categories of this paper are: chao-dyn
5
The categories of this paper are: gr-qc
37
The categories of this paper are: supr-con
28
The categories of this paper are: alg-geom
8
The categories of this paper are: hep-ex
13
The categories of this paper are: quant-ph
21
The categories of this paper are: adap-org
17
The categories of this paper are: q-fin
1
The categories of this paper are: cs
29
The categories of this paper are: funct-an
19
The categories of this paper are: eess
30
The categories of this paper are: q-alg
15
The categories of this paper are: nucl-ex
32
The categories of this paper are: atom-ph
16
The categories of this paper are: stat
31
The categories of this paper are: ao-sci