Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum Transition from Order to Chaos in the Nuclear Shell Model   We discuss the role of quantum chaos in atomic nuclei. After reviewing the
basic assumptions of the nuclear shell model, we analyze the spectral
statistics of the energy levels obtained with realistic shell-model
calculations in the fp shell. In particular, for Ca isotopes we observe a
transition from order to chaos by increasing the excitation energy and a clear
quantum signature of the breaking of integrability by changing the
single-particle spacings.

24
The categories of this paper are: dg-ga
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The categories of this paper are: patt-sol
20
The categories of this paper are: acc-phys
21
The categories of this paper are: adap-org
16
The categories of this paper are: stat
36
The categories of this paper are: cmp-lg
0
The categories of this paper are: hep-ph
3
The categories of this paper are: physics
7
The categories of this paper are: hep-th
32
The categories of this paper are: atom-ph
35
The categories of this paper are: mtrl-th
18
The categories of this paper are: econ
14
The categories of this paper are: math-ph
31
The categories of this paper are: ao-sci
10
The categories of this paper are: q-bio
15
The categories of this paper are: nucl-ex