Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Precision mass measurements of neutron-rich scandium isotopes refine the
  evolution of $N=32$ and $N=34$ shell closures   We report high-precision mass measurements of $^{50-55}$Sc isotopes performed
at the LEBIT facility at NSCL and at the TITAN facility at TRIUMF. Our results
provide a substantial reduction of their uncertainties and indicate significant
deviations, up to 0.7 MeV, from the previously recommended mass values for
$^{53-55}$Sc. The results of this work provide an important update to the
description of emerging closed-shell phenomena at neutron numbers $N=32$ and
$N=34$ above proton-magic $Z=20$. In particular, they finally enable a complete
and precise characterization of the trends in ground state binding energies
along the $N=32$ isotone, confirming that the empirical neutron shell gap
energies peak at the doubly-magic $^{52}$Ca. Moreover, our data, combined with
other recent measurements, does not support the existence of closed neutron
shell in $^{55}$Sc at $N=34$. The results were compared to predictions from
both \emph{ab initio} and phenomenological nuclear theories, which all had
success describing $N=32$ neutron shell gap energies but were highly disparate
in the description of the $N=34$ isotone.

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The categories of this paper are: acc-phys
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The categories of this paper are: stat
6
The categories of this paper are: astro-ph
9
The categories of this paper are: nlin
4
The categories of this paper are: cond-mat
7
The categories of this paper are: hep-th
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The categories of this paper are: solv-int
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The categories of this paper are: patt-sol
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The categories of this paper are: ao-sci
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The categories of this paper are: bayes-an
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The categories of this paper are: quant-ph
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The categories of this paper are: q-alg
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The categories of this paper are: mtrl-th
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The categories of this paper are: gr-qc
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The categories of this paper are: eess
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The categories of this paper are: supr-con