Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Measurement of $^{58}$Ni($p$, $p$)$^{58}$Ni elastic scattering at low
  momentum transfer by using the HIRFL-CSR heavy-ion storage ring   The very first in-ring reaction experiment at the HIRFL-CSR heavy-ion storage
ring, namely proton elastic scattering on stable $^{58}$Ni nuclei, is
presented. The circulating $^{58}$Ni$^{19+}$ ions with an energy of 95 MeV/u
were interacting repeatedly with an internal hydrogen gas target in the CSRe
experimental ring. Low energy proton recoils from the elastic collisions were
measured with an ultra-high vacuum compatible silicon-strip detector. Deduced
differential cross sections were normalized by measuring K-shell X-rays from
$^{58}$Ni$^{19+}$ projectiles due to the $^{58}$Ni$^{19+}$-H$_2$ ionization
collisions. Compared to the experimental cross sections, a good agreement has
been achieved with the theoretical predictions in the measured region, which
were obtained by using the global phenomenological optical model potentials.
Our results enable new research opportunities for optical model potential
studies on exotic nuclides by using the in-ring reaction setup at the HIRFL-CSR
facility.

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The categories of this paper are: econ
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The categories of this paper are: patt-sol
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The categories of this paper are: q-fin
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The categories of this paper are: acc-phys
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The categories of this paper are: chem-ph
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The categories of this paper are: plasm-ph
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The categories of this paper are: cs
4
The categories of this paper are: cond-mat
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The categories of this paper are: quant-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: cmp-lg
0
The categories of this paper are: hep-ph
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The categories of this paper are: math
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The categories of this paper are: nucl-th
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The categories of this paper are: hep-ex
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The categories of this paper are: gr-qc