Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Anisotropic $e^+ e^-$ pressure due to the QED effect in strong magnetic
  fields and the application to the entropy production in neutrino-driven wind   We study the equation of state of electron in strong magnetic fields which
are greater than the critical value $B_c \simeq 4.4 \times 10^{13}$ Gauss. We
find that such a strong magnetic field induces the anisotropic pressure of
electron. We apply the result to the neutrino-driven wind in core-collapse
supernovae and find that it can produce large entropy per baryon, $S \sim 400
k_B$. This mechanism might successfully account for the production of the heavy
nuclei with mass numbers A = 80 -- 250 through the r-process nucleosynthesis.

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The categories of this paper are: cond-mat
37
The categories of this paper are: supr-con
12
The categories of this paper are: nucl-th
16
The categories of this paper are: stat
21
The categories of this paper are: adap-org
31
The categories of this paper are: ao-sci
33
The categories of this paper are: plasm-ph
1
The categories of this paper are: cs
19
The categories of this paper are: eess
5
The categories of this paper are: gr-qc
18
The categories of this paper are: econ
10
The categories of this paper are: q-bio
32
The categories of this paper are: atom-ph
3
The categories of this paper are: physics
27
The categories of this paper are: comp-gas
28
The categories of this paper are: alg-geom