Shape evolution and coexistence in neutron-deficient Kr, Rb, Sr and Zr nuclei

Exploring the halo phenomena of medium-mass nuclei having approximately Z= 40 with point-coupled parameters in complex momentum representations *

“…Moreover, although the deformation process is stable for Kr isotopes, it is unstable for Zr and Sr isotopes. In addition, in the quadrupole deformation space ( ), several cases of γ-soft behavior are predicted for and [14][15][16][17][18]. Correspondingly, some of these theoretical conclusions also correspond to the experimental results [19][20][21].…”

Mixing of the coexisting shapes in the ground states of 74Ge and 74Kr

“…The often overlooked fact is that the same simple two-level model which explains this relationship, suggests that in the strong mixing situation the energy difference between the corresponding observable states greatly reduces. As reports on shape coexistence in à 70 region presently abound [3][4][5][6][7][8][9][10][11][12][13][14][15][29][30][31][32][33][34], the investigation of these signatures in some isotopic chains is possible and could lead to useful correlations which can steer future theoretical and experimental shape coexistence studies [3,10,13,30,31,35]. Thus, studying the relevant spectroscopic information for Ge, Se and Kr, one observed that the evolution of the aforementioned observables within isotopic chains is synced in respect to the mass number.…”

“…The wealth of data for these nuclei and their neighbouring isotopes as well as their well-established shape coexisting structure [3][4][5][6][7][8][9][10][11][12][13][14][15][29][30][31][32][33][34] can be used to search other spectral signatures which are correlated with this phenomenon. This is essential because, in general, data on excited + 0 states is usually unavailable for many nuclei of interest.…”

“…The region Z 34 and Ñ 40 of shape coexistence is most afflicted by mixing [3,4], and the best venue to study this phenomenon. To this goal, one investigates here the shape and deformation properties of 74 Ge and 74 Kr nuclei known for having mixed coexisting shapes in their ground state [3][4][5][6][7][8][9][10][11][12][13][14][15]. The two nuclei are important also from the point of view of shape phase transitions, being considered as critical nuclei in the transition from oblate to prolate shapes in their isotopic chains [12][13][14][15][16][17][18][19].…”