286
8 Manifestations of Chaos in Quantum Scattering Processes
Fig. 8.14 Four level
sequences, each containing 50
levels scaled to have the same
range and average spacing.
(a) From slow neutron
resonance of 166 Er. (b) From
the proton resonance region
of 168 Ti. (c) Poisson random
levels. (d) From the slow
neutron resonance region of
181 Ta. The arrows indicate
spacing less than one-quarter
of the average spacing (Brody
et al. 1981)
Fig. 8.15 Nearest neighbor spacing histograms for the same sequences as in Fig. 8.14 but using
all data available. The solid line is the Wigner distribution and the dashed line is the Poisson
distribution (Brody et al. 1981)