Yrast structure of ${}^{64}\mathrm{Fe}$

The level structure of the $N=38$ isotone ${}^{64}\mathrm{Fe}$ was studied with the ${}^{64}\mathrm{Ni}$ + ${}^{238}\mathrm{U}$ reaction at 430 MeV. Several new levels were identified and compared to shell model calculations. Results show no evidence for deformation in the ground state, but a possible contribution from intruder orbitals at higher energy and spin.

Figure 1

The 2${}^{+}$ energy trends for selected nuclides near ${}^{68}\mathrm{Ni}$.

Figure 2

(a) The γ-ray spectrum obtained by setting a single gate at 746 keV in the data from the deep-inelastic reaction of ${}^{64}\mathrm{Ni}$ and ${}^{238}\mathrm{U}$. (b) The spectrum obtained from a double gate on 746- and 1017-keV γ rays in data from the deep-inelastic reaction of ${}^{48}\mathrm{Ca}$ and ${}^{208}\mathrm{Pb}$ [18].

Figure 3

The γ-ray spectrum obtained by setting a double gate on 746- and 1017-keV γ rays. The inset shows portions of spectra obtained from 746-582 (top) and 746-781 (bottom) double gates.

Figure 4

The proposed level scheme for ${}^{64}\mathrm{Fe}$ compared with shell model calculations (see text for details). Included with the experimental levels are three low-energy levels reported by Hannawald [20].

Figure 5

Angular correlation curves for the 1017-keV transition and high- and low-energy components of the 1078-keV doublet. Each point was determined by fitting the 746-keV peak in the respective gates denoted in each plot.

Figure 6

Levels in the $N=38$ isotones.