Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Large Shell Model Calculations for Calcium Isotopes: Spectral Statistics
  and Chaos   We perform large shell model calculations for Calcium isotopes in the full fp
shell by using the realistic Kuo-Brown interaction. The Calcium isotopes are
especially interesting because the nearest-neighbour spacing distribution P(s)
of low-lying energy levels shows significant deviations from the predictions of
the Gaussian Orthogonal Ensemble of random--matrix theory. This contrasts with
other neighbouring nuclei which show fully chaotic spectral distributions. We
study the chaotic behaviour as a function of the excitation energy. In
addition, a clear signature of chaos suppression is obtained when the
single-particle spacings are increased. In our opinion the relatively weak
strength of the neutron-neutron interaction is unable to destroy the regular
single-particle mean-field motion completely. In the neighbouring nuclei with
both protons and neutrons in valence orbits, on the other hand, the stronger
proton-neutron interaction would appear to be sufficient to destroy the regular
mean-field motion.

32
The categories of this paper are: atom-ph
0
The categories of this paper are: hep-ph
34
The categories of this paper are: chem-ph
21
The categories of this paper are: adap-org
7
The categories of this paper are: hep-th
13
The categories of this paper are: quant-ph
22
The categories of this paper are: chao-dyn
35
The categories of this paper are: mtrl-th
30
The categories of this paper are: q-alg
19
The categories of this paper are: eess
2
The categories of this paper are: math
8
The categories of this paper are: hep-ex
9
The categories of this paper are: nlin
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
25
The categories of this paper are: patt-sol