This article presents numerical results on the distribution ol nearest-neighbor level spac-ings Shd the avoided crossing behavior of quanitum energy curves for a cpupled spin model coming from nuclear many body theory. When the system undergoes a transition from classical regular to chaos and then to regular as varying a model parameter,the Brody parameter of the level spacing distribution p(s) could be fairly associated to the fraction of classical chaotic tra-jectories in phase space.;ln the regime of parameters with large chaotic regions, a number of overlapping avoided crossings were discovered from the results of computations, Which lead the energy curves looked irregular These results are considered as quantum manifestation or ‘scars' pf classidal chaos in spectrum.
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