Study of neutron-rich nuclei in the vicinity of the doubly magic core of 132Sn
Jeudi 2 octobre 2014 10:30
- Duree : 2 heures
Lieu : Amphithéâtre du LPSC - 53 rue des Martyrs - Grenoble
Orateur : Soutenance de Thèse de Guillaume GEY (ILL/LPSC)
The evolution of nuclear structure in the vicinity of the doubly magic nuclei 132Sn will be discussed, through the spectroscopy of 13651Sb85, 13650Sn86 and 13850Sn88 isotopes. Several Sb and Sn known isotopes beyond the Z=50 and N=82 shell closures will be briefly presented, as well as some of the problems arising from the current shell-model description of the nuclei in this region. A brief introduction to the shell model and effective interactions will also be given.
Excited states of 136Sb have been populated at the Institut Laue-Langevin (Grenoble) through thermal neutron-induced fission on a 241Pu target. The fission fragments produced were separated with the Lohengrin mass spectrometer. Delayed conversion electrons and gamma-rays from 136Sb were measured and confirmed the previously proposed schemed. A new 31(7) ns isomer has been measured and assigned to the 4- state. Details of the experiment and analysis will be presented in the second part.
The third part will be devoted to the 136, 138Sn isotopes, produced via in-flight fission of 238U on a 9Be target at the RIBF of the RIKEN (Tokyo). The mass separators BigRIPS and ZDS allowed separation and identification of the produced fragments, before implantation in the highly segmented silicon detector WAS3ABi surrounded by the EURICA germanium array. The first energy measurement of the 6+ → 4+, 4+ → 2+ and 2+ → 0+ transitions has been performed for each of the 136,138Sn isotopes, as well as 46(7) and 219(58) ns half-lives for the 6+ states of the 136Sn and 138Sn respectively.
Contact : blanc@ill.fr
Prévenir un ami par email
Télécharger dans mon agenda
RSS 2.0 : Tous les evenements