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تسجيل مستخدم جديدThe population of deformed bands in $^{48}$Cr by emission of $^{8}$Be from the $^{32}$S + $^{24}$Mg reaction
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Using particle-$gamma$ coincidences we have studied the population of final states after the emission of 2 $alpha$-particles and of $^{8}$Be in nuclei formed in $^{32}$S+$^{24}$Mg reactions at an energy of $textrm{E}_{rm L}(^{32}textrm{S}) = 130 {rm MeV}$. The data were obtained in a setup consisting of the GASP $gamma$-ray detection array and the multidetector array ISIS. Particle identification is obtained from the $Delta$E and E signals of the ISIS silicon detector telescopes, the $^{8}$Be being identified by the instantaneous pile up of the $Delta$E and E pulses. $gamma$-ray decays of the $^{48}$Cr nucleus are identified with coincidences set on 2 $alpha$-particles and on $^{8}$Be. Some transitions of the side-band with $K^pi=4^{-}$ show stronger population for $^{8}$Be emission relative to that of 2 $alpha$-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.
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