Quasivibrational Bands at High Spins inYb158

Autor: Y. Schutz, L.H. Courtney, I. Y. Lee, C. Baktash, A. J. Larabee, M.P. Fewell, D. G. Sarantites, Noah R. Johnson, O. C. Kistner, M. L. Halbert, D. C. Hensley, F. K. McGowan, A.W. Sunyar, der Mateosian E, L. L. Riedinger
Rok vydání: 1985
Předmět:
Zdroj: Physical Review Letters. 54:978-981
ISSN: 0031-9007
DOI: 10.1103/physrevlett.54.978
Popis: High-spin states in the transitional nucleus $^{158}\mathrm{Yb}$ were populated via several (HI, $4n$) reactions. Two yrast bands were established up to ${I}^{\ensuremath{\pi}}=({40}^{+}) \mathrm{and} ({31}^{\ensuremath{-}})$. In contrast to the negative-parity band up to $I=31$ and the positive-parity states up to $I=24$ which show collective rotational patterns, states with ${I}^{\ensuremath{\pi}}={26}^{+}\ensuremath{-}{36}^{+}$ exhibit a nearly vibrational excitation mode. Such a quasivibrational pattern suggests a gradual transition toward oblate shapes and is the first evidence for a "band termination" in a heavy nucleus.
Databáze: OpenAIRE