Level densities of ${}^{44}\mathrm{Sc}$ and ${}^{47}\mathrm{Ti}$ from different experimental techniques

The level densities of ${}^{44}\mathrm{Sc}$ and ${}^{47}\mathrm{Ti}$ have been determined from measurements of particle evaporation spectra from the compound nuclear reaction ${}^3\mathrm{He}+{}^{45}\mathrm{Sc}$ with an 11 MeV ${}^3\mathrm{He}$ beam. The level density of ${}^{44}\mathrm{Sc}$ has been compared to the level density obtained from an independent experimental method based on an analysis of $\alpha \text{−}\gamma$ coincidences from the transfer reaction ${}^{45}\mathrm{Sc}$(${}^3\mathrm{He}$,$\alpha \gamma$)${}^{44}\mathrm{Sc}$. The good agreement between the two experiments indicates the reliability of the level density obtained. Some level density systematics have been tested against the experimental data. New Fermi-gas level density parameters have been derived.

Figure 1

Angular distributions of α particles in the c.m. system for different energy intervals. The points are experimental data and the solid lines are HF calculations normalized to match the experimental points at backward angles for low energy particles.

Figure 2

Angular distributions of protons (open circles) and α particles (solid circles) in the c.m. system.

Figure 3

Experimental energy spectra of protons and α particles measured at ${157}^{°}$ with respect to the beam line.

Figure 4

Level densities of ${}^{47}\mathrm{Ti}$ (upper panel) and ${}^{44}\mathrm{Sc}$ (lower panel) nuclei obtained from proton and α-particle energy spectra, respectively. Black points are data from particle evaporation spectra. Open points are data from the Oslo experiment [7]. The histograms represent level densities from the counting of discrete levels.