High-spin states in doubly odd176Reand signature inversion inπh9/2

Abstract

High-spin states in doubly odd 176 Re were investigated by means of in-beam ␥-ray spectroscopy techniques using the multidetector array GASP. Excited states of 176 Re were populated using the 165 Ho( 16 O,5n) reaction at a beam energy of 101 MeV. Seven rotational bands have been observed and their configurations have been discussed. Alignments, band crossing frequencies, and electromagnetic properties have been analyzed in the framework of the cranking model. Signature inversion phenomena in the h 11/2 i 13/2 and h 9/2 i 13/2 structures are discussed. In the latter case signature inversion is traced to a large repulsive matrix element of the pϪn force acting in the maximally aligned Jϭ11 state.

High-spin states in odd-odd174Re

“…Similar isomeric states have been observed in 176 Re[4] and 176 Ir[30]. The isomeric lifetime can be roughly estimated by using the experimental internal conversion coefficient 0.62, the theoretical internal conversion coefficient 0.27, and the time window of 200 ns: 91 ns.…”

“…These values are taken from the compilation in Refs. [4,44] and can be found in Table III. Concerning the quadrupole moment, we refer to Q 0 = 7.3 eb of the groundstate band in 172 W [45].…”

“…Odd-A nuclei show many interesting high-spin phenomena, such as signature splitting, deformation driving effects, e.g., changes in deformation due to the occupation of specific orbitals by the odd nucleon, and so on. For odd-odd nuclei, the system becomes more complex due to a variety of coupling schemes among the valence nucleons and the core; some new phenomena appear such as the well-known low-spin signature inversion in a number of two-quasiparticle bands built on the πh 11/2 ⊗ νi 13/2 and πh 9/2 ⊗ νi 13/2 configurations [1][2][3][4][5][6][7]. The nuclei in the lighter W-Re-Os region are rather soft with respect to both the β and γ deformations.…”

Low-spin signature inversion in theπh9/2⊗νi13/2oblate band ofXie1, Zhou2, Zhang3 et al. 2005Phys. Rev. C11070View full textAdd to dashboardCite

“…Low-spin signature inversion has been systematically observed in deformed odd-odd nuclei throughout the chart of nuclides (see Refs. [2,[4][5][6][7][8][9][10], and references therein), related to the high-j πg 9/2 ⊗ νg 9/2 , πh 11/2 ⊗ νh 11/2 , πh 11/2 ⊗ νi 13/2 , πh 9/2 ⊗ νi 13/2 , and πi 13/2 ⊗ νi 13/2 configurations. Great theoretical efforts have been devoted to the understanding of low-spin signature inversion in deformed odd-odd nuclei.…”

“…Great theoretical efforts have been devoted to the understanding of low-spin signature inversion in deformed odd-odd nuclei. Nuclear triaxiality and protonneutron residual interaction have been proposed as possible reasons for the inversion phenomenon [2,6,7,[11][12][13][14]. Furthermore, theoretical studies have suggested that the occurrence of signature inversion is associated closely with * Electronic address: zxh@impcas.ac.cn the positions of the Fermi surfaces of nucleons [2,15] and the configurations of states [14].…”