Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Proton-Proton Reaction, Solar Neutrinos, and a Relativistic Field
  Theoretic Model of the Deuteron   In a series of recent papers, Ivanov et al. and Oberhummer et al. have
calculated the rate for the $p + p \to d + e^+ + \nu_e$ reaction with a
zero-range four-fermion effective interaction and find a result 2.9 times
higher than the standard value calculated from non-relativistic potential
theory. Their procedure is shown to give a wrong answer because their assumed
interaction disagrees with low-energy $pp$ scattering data.

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The categories of this paper are: eess
8
The categories of this paper are: hep-ex
3
The categories of this paper are: physics
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
4
The categories of this paper are: cond-mat
18
The categories of this paper are: econ
29
The categories of this paper are: funct-an
30
The categories of this paper are: q-alg
28
The categories of this paper are: alg-geom
13
The categories of this paper are: quant-ph
37
The categories of this paper are: supr-con
9
The categories of this paper are: nlin
11
The categories of this paper are: hep-lat
5
The categories of this paper are: gr-qc
7
The categories of this paper are: hep-th