Shell-model states and collectivity in⁸³Br₄₈and⁸⁵Rb₄₈

Magnetic dipole sequences inRb83

“…For the slowing-down the cross sections given in Ref. [47] were used with correction factors of f e = 0.9 and f n = 0.7 for the electronic and nuclear stopping powers, respectively [8,13,33,[48][49][50]. To extract the level lifetimes, cascade feeding from all levels observed above the considered one as well as sidefeeding from unobserved levels was taken into account.…”

“…[7]. With decreasing excitation energy an increase of the sidefeeding times according to τ sf = (E * − E/MeV) × 0.03 ps was assumed [8,13,33,[48][49][50]. Examples of the line-shape analysis are shown in Fig.…”

“…Because a complete empirical set of effective interactions for this model space has not been available until now, various empirical interactions have been combined with schematic nuclear interactions applying the surface delta interaction. Details of this procedure are described in our previous shell-model studies of nuclei with N = 47 − 54 [13,33,49,50,[55][56][57][58][59][60][61][62][63]. This is the first attempt to apply this model space and set of interactions to an N = 46 nuclide.…”

“…First discovered in 81 Kr [1,2], they were also observed in the isotopes 79,83 Kr [3,4], in the neighboring odd-N nuclide 83 Sr [5], and in the odd-Z nuclides 77,79,81 Br [6][7][8][9] and 79,81,83,85 Rb [10][11][12][13]. At that time, the strong M1 transitions were interpreted in the framework of a semiclassical coupling scheme for the spins of the involved nucleons [1,2].…”

86Sr states homologous to the low-lying states of 85Rb

“…In literature is reported a shell model study of SSRb [6], concerning essentially high spin states. On the contrary, our interest is devoted to low-lying levels that only can be parent states able to produce multiplets of homologous states at not too high excitation energies.…”