Institut de recherche sur les lois fondamentales de l'Univers

Direction de la recherche fondamentale

Résumé du preprint DAPNIA-06-175

DAPNIA-06-175
Competition between collective and noncollective excitation modes at high spin in 124Ba
A.Al-Khatib, A.K.Singh, H.Huebel, P.Bringel, A.Buerger, J.Domscheit, A.Neusser-Neffgen, G.Schoenwasser, G.B.Hagemann, C. Ronn-Hansen, B.Herskind, G.Sletten, J.N.Wilson, J.Timar, A.Algora, Zs.Dombradi, J.Gal, G.Kalinka, J.Molnar, B.M.Nyako, D.Sohler, L.Zolnai, R.M.Clark, M.Cromaz, P.Fallon, I.Y.Lee, A.O.Macchiavelli, D.Ward, H.Amro, W.C.Ma, M.Kmiecik, A.Maj, J.Styczen, K.Zuber, K.Hauschild, A.Korichi, A.Lopez-Martens, J.Roccaz, S.Siem, F.Hannachi, J.N.Scheurer, P.Bednarczyk, Th.Byrski, D.Curien, O.Dorvaux, G.Duchene, B.Gall, F.Khalfallah, I.Piqueras, J.Robin, A.Goergen, K.Juhasz, S.B.Patel, A.O.Evans, G.Rainovski, G.Benzoni, A.Bracco, F.Camera, S.Leoni, P.Mason, B.Million, A.Paleni, R.Sacchi, O.Wieland, C.M.Petrache, D.Petrache, G.La Rana, R.Moro, G.De Angelis, J.C.Lisle, B.Cederwall, K.Lagergren, R.M.Lieder, E.Podsvirova, W.Gast, H.Jaeger, N.Redon
High-spin states in 124Ba were investigated in two experiments using the 64Ni(64Ni,4n)124Ba reaction at three different beam energies. In-beam gamma-ray coincidences were measured with the Euroball and Gammasphere detector arrays. In the experiment with Euroball, the CsI detector array Diamant was employed to discriminate against charge-particle channels. Six new rotational bands were observed in 124Ba, and previously known bands were extended to higher spins. One of the bands shows a transition from collective to noncollective behavior at high spins. Configuration assignments are suggested on the basis of comparison with cranked shell model and cranked Nilsson-Strutinsky calculations.