The population of deformed bands in ${}^{48}$Cr by emission of ${}^8$Be from the ${}^{32}$S + ${}^{24}$Mg reaction

Abstract

Using particle-${\hat{I}}^3$ coincidences we have studied the population of final states after the emission of 2 $\hat{I}\pm$-particles and of ${}^8$Be in nuclei formed in ${}^{32}$S+${}^{24}$Mg reactions at an energy of ${\text{E}}_{\mathrm{L}}{(}^{32}\text{S})=130\mathrm{MeV}$. The data were obtained in a setup consisting of the GASP ${\hat{I}}^3$-ray detection array and the multidetector array ISIS. Particle identification is obtained from the $\hat{I}”$E and E signals of the ISIS silicon detector telescopes, the ${}^8$Be being identified by the instantaneous pile up of the $\hat{I}”$E and E pulses. ${\hat{I}}^3$-ray decays of the ${}^{48}$Cr nucleus are identified with coincidences set on 2 $\hat{I}\pm$-particles and on ${}^8$Be. Some transitions of the side-band with $K^{\ddot{I}}€=4^{-}$ show stronger population for ${}^8$Be emission relative to that of 2 $\hat{I}\pm$-particles (by a factor $1.5-1.8$). This observation is interpreted as due to an enhanced emission of ${}^8$Be into a more deformed nucleus. Calculations based on the extended Hauser-Feshbach compound decay formalism confirm this observation quantitatively.

17 pages, 9 figures accepted for publication in J. Phys. G