PHENIICS Doctoral School Days

Study of neutron monopole drift towards 78Ni with AGATA at GANIL and BEDO at ALTO

10 mai 2016, 10:15

1h

Auditorium Pierre Lehmann (Laboratoire de l'Accélérateur Linéaire (LAL))

Panneau: 59

Poster Nuclear Physics Poster session

Orateur

M. Clément DELAFOSSE (IPNO)

Description

Recent experimental discoveries have revealed that the neutron effective single particle evolution above ${}^{78}$Ni shows peculiar and unpredicted behaviours. Our study us mainly focussed on the neutron $g_{7/2}$ effective single particle energy (ESPE) evolution towards ${}^{78}$Ni. This evolution should be driven by the same tensor mechanism which produces a quasi-degeneracy of the $d_{5/2}$-$g_{7/2}$ orbits in the ${}^{100}$Sn region. The light odd-neutron N=51 nuclei constitute the most interesting cases in order to study this evolution and constrain theoretical models. We have performed two complementary experiments to populate ${\frac{7}{2}}^{+}$ states in ${}^{83}$Ge, one in flight experiment at GANIL, using the fusion-fission Be+${}^{238}$U reaction to populate Yrast states, one ISOL experiment at ALTO using the decay of ${}^{83}$Ga to populate non-Yrast states. The experiment at GANIL was made with AGATA, VAMOS and a plunger which permit to distinguish single particle (long lived) or collective (short lived) origin of potential ${\frac{7}{2}}^{+}$ state. The experiment at ALTO used the Compton suppressed gamma spectrometer BEDO including 2 tapered and 2 clovers of HPGe. In this poster, the physics motivation, the experimental arrangements and preliminary results will be presented.