Lifetime measurements in the chiral-candidate doublet bands of La130
Makaleler > Tam Makale · 2018
Yazarlar: M. Ionescu-Bujor, S. Aydin, N. Mărginean, C. Costache, D. Bucurescu, N. Florea, T. Glodariu, A. Ionescu, A. Iordăchescu, R. Mărginean, C. Mihai, R. E. Mihai, A. Mitu, A. Negreţ, C. R. Niţă, A. Olăcel, S. Pascu, B. Saygi, L. Stroe, R. Suvăilă, S. Toma, A. Turturică
Physical Review C, Uluslararası, Wos, 2018, cilt 98
DOI: 10.1103/physrevc.98.054305
Özet
The lifetimes of the excited states belonging to the chiral-candidate doublet bands built on the $\ensuremath{\pi}{h}_{11/2}\ensuremath{\bigotimes}\ensuremath{\nu}{h}_{11/2}^{\ensuremath{-}1}$ configuration in $^{130}\mathrm{La}$ have been measured by applying the Doppler-shift attenuation method and the in-beam fast timing technique. Excited states were populated in the $^{121}\mathrm{Sb}(^{12}\mathrm{C},3n)$ reaction at a bombarding energy of 54 MeV. The ${7}^{+}$ bandhead of the yrast band was identified as an isomeric state with a lifetime of $\ensuremath{\tau}({7}^{+})=0.38(7)\phantom{\rule{0.16em}{0ex}}\mathrm{ns}$. Similar reduced transition probabilities $B(M1)$ and $B(E2)$ were found for the states with the same spin in the partner bands. The results revealed an even-odd spin dependence in the $B(E2)$ values, whereas the $B(M1)$ values vary nearly monotonically with increasing spin. The experimental properties of the doublet bands in $^{130}\mathrm{La}$ are compared with theoretical calculations done in the frame of the two-quasiparticles-plus-triaxial-rotor model. The static chirality is not supported by the obtained data; however, chiral vibrations cannot be excluded.