Author/Authors :
P. Petkov، نويسنده , , A. Dewald، نويسنده , , R. Kühn، نويسنده , , R. Peusquens، نويسنده , , D. Tonev، نويسنده , , S. Kasemann، نويسنده , , K.O. Zell، نويسنده , , P. von Brentano، نويسنده , , D. Bazzacco، نويسنده , , C. Rossi-Alvarez، نويسنده , , G. De Angelis، نويسنده , , S. Lunardi، نويسنده , , P. Pavan، نويسنده , , D.R. Napoli، نويسنده ,
Abstract :
The lifetimes of five levels of the two-quasineutron band in 128Ba populated via the 116Cd(16O,4n) reaction were measured for the first time by means of the recoil-distance Doppler-shift method. For the data-analysis, a new version of the differential decay-curve method in singles-like mode was developed which takes into account the velocity distribution of the recoils and the effect of the Doppler-shift attenuation in the stopper. The high values of 〈K2〉 and View the MathML source characterising the band are confirmed by the determined B(E2,I→I−2) and B(M1,I→I−1) transition strengths. At the same time, the rigid-rotor model is not able to describe the behaviour of the experimental B(E2,I→I−1) and B(M1,I→I−1) values. A new theoretical effort seems to be needed for a consistent explanation of the intraband transition strengths within two-quasiparticle bands in γ-soft nuclei.
Keywords :
Nuclear reaction116Cd(16O , Measured View the MathML source , 4n) , recoil-distance Doppler-shift , 128Ba levels deduced ? , Enriched target , Ge detectors , Velocity distribution , line-shape analysis with Doppler-shift attenuation effects , differential decay-curve analysis , Comparison of intraband E2 and M1 transition strengths within the two-quasineutron band to theoretical predictions , E=76 MeV , B(?)
