Monopole-driven shell evolution below the doubly magic nucleus Sn explored with the long-lived isomer in Pd
Watanabe, H.*; Lorusso, G.*; Nishimura, Shunji*; Otsuka, T.*; Ogawa, K.*; Xu, Z. Y.*; Sumikama, Toshiyuki*; Sderstrm, P.-A.*; Doornenbal, P.*; Li, Z.*; Browne, F.*; Gey, G.*; Jung, H. S.*; Taprogge, J.*; Vajta, Zs.*; Wu, J.*; Yagi, A.*; Baba, Hidetada*; Benzoni, G.*; Chae, K. Y.*; Crespi, F. C. L.*; Fukuda, Naoki*; Gernhuser, R.*; Inabe, Naoto*; Isobe, T.*; Jungclaus, A.*; Kameda, Daisuke*; Kim, G. D.*; Kim, Y.-K.*; Kojouharov, I.*; Kondev, F. G.*; Kubo, Toshiyuki*; Kurz, N.*; Kwon, Y. K.*; Lane, G. J.*; Moon, C.-B.*; Montaner-Piz, A.*; Moschner, K.*; Naqvi, F.*; Niikura, Megumi*; Nishibata, Hiroki*; Nishimura, Daiki*; Odahara, Atsuko*; Orlandi, R. ; Patel, Z.*; Podolyk, Zs.*; Sakurai, Hiroyoshi*; Schaffner, H.*; Simpson, G. S.*; Steiger, K.*; Suzuki, H.*; Takeda, H.*; Wendt, A.*; Yoshinaga, Kenta*
A new isomer with a half-life of 23.0(8) ms has been identified in Pd at 2406 keV excitation. The proposed spin and parity configuration is 10, with maximally aligned configuration of two neutron hole. -decay from the long-lived isomer was also observed to populated excited states at high spins in Ag. The small energy difference between the 10 and 7 isomers in Pd was interpreted in the frame of the monopole shift of the 1 neutron orbit. The effects of the monopole interaction on the evolution of single-neutron energies below Sn are discussed in terms of central and tensor forces.