Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Localized Optical Vortex Solitons in Pair Plasmas   The dynamics of short intense electromagnetic pulses propagating in a
relativistic pair plasma with small temperature asymmetry is of current
interest. Such pulses were shown to be governed by a nonlinear Schrodinger
equation with a new type of focusing-defocusing nonlinearity. We provide an
existence theory and numerical analysis for a special class of solutions, known
as "ring-profiled" optical vortex solitons. Our methods include both a direct
and constrained minimization. We give a necessary condition for the existence
of nontrivial solutions and a series of interesting estimates in terms of the
relevant parameters describing the electromagnetic pulse. Additionally, we use
the constrained minimization approach and a finite element formalism to
numerically study the behavior of the profiles of soliton solutions.

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The categories of this paper are: astro-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: solv-int
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The categories of this paper are: gr-qc
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The categories of this paper are: supr-con
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The categories of this paper are: cond-mat
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The categories of this paper are: cmp-lg
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The categories of this paper are: dg-ga
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The categories of this paper are: nucl-ex
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The categories of this paper are: bayes-an
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The categories of this paper are: alg-geom
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The categories of this paper are: chem-ph
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The categories of this paper are: q-bio
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The categories of this paper are: hep-ex
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The categories of this paper are: q-fin
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The categories of this paper are: hep-th