Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the electrostatic field of a tokamak in the limit of large aspect
  ratio and concentric circular flux surfaces   From a common expression for the poloidal electrostatic field of a tokamak,
in the limit of large aspect ratio and concentric circular flux surfaces, one
may determine the associated potential. This potential satisfies Poisson's
equation, which reduces to Laplace's equation when the medium has vanishing
charge density, in axial geometry but not toroidal geometry. A simple
transformation takes the potential over to the correct harmonic form for
tokamak coordinates, and the resulting electrostatic field is calculated. From
the radial field one may estimate the supporting charge density on the
boundary, and from the poloidal field one may determine a prediction for the
radial dependence of the electron temperature, which does not compare well with
a rough estimate of the profile often seen in a tokamak.

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The categories of this paper are: plasm-ph
0
The categories of this paper are: hep-ph
7
The categories of this paper are: hep-th
24
The categories of this paper are: dg-ga
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The categories of this paper are: chem-ph
9
The categories of this paper are: nlin
19
The categories of this paper are: eess
23
The categories of this paper are: solv-int
4
The categories of this paper are: cond-mat
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The categories of this paper are: cmp-lg
15
The categories of this paper are: nucl-ex
13
The categories of this paper are: quant-ph
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The categories of this paper are: ao-sci
8
The categories of this paper are: hep-ex
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg