proton-hole state in Sn and the shell structure along =82

Taprogge, J.*; Jungclaus, A.*; Grawe, H.*; Nishimura, Shunji*; Doornenbal, P.*; Lorusso, G.*; Simpson, G.*; Sderstrm, P.-A.*; Sumikama, Toshiyuki*; Xu, Z. Y.*; Baba, Hidetada*; Browne, F.*; Fukuda, Naoki*; Gernhuser, R.*; Gey, G.*; Inabe, Naoto*; Isobe, T.*; Jung, H. S.*; Kameda, Daisuke*; Kim, G. D.*; Kim, Y.-K.*; Kojouharov, I.*; Kubo, Toshiyuki*; Kurz, N.*; Kwon, Y. K.*; Li, Z.*; Sakurai, Hiroyoshi*; Schaffner, H.*; Steiger, K.*; Suzuki, H.*; Takeda, H.*; Vajta, Zs.*; Watanabe, H.*; Wu, J.*; Yagi, A.*; Yoshinaga, Kenta*; Benzoni, G.*; Bnig, S.*; Chae, K. Y.*; Coraggio, L.*; Covello, A.*; Daugas, J.-M.*; Drouet, F.*; Gadea, A.*; Gargano, A.*; Ilieva, S.*; Kondev, F. G.*; Krll, T.*; Lane, G. J.*; Montaner-Piz, A.*; Moschner, K.*; Mcher, D.*; Naqvi, F.*; Niikura, Megumi*; Nishibata, Hiroki*; Odahara, Atsuko*; Orlandi, R.  ; Patel, Z.*; Podolyk, Zs.*; Wendt, A.*

A low-lying state in In, the one-proton hole nucleus with respect to double magic Sn, was observed by its decay to the beta emitting isomer. The new state, which was populated both in the beta decay of Cd and after beta-delayed neutron emission from Cd, was identified, at an excitation energy of 1353 keV, as the previously unknown single-hole state with respect to the Sn core. Exploiting this crucial new experimental information, shell-model calculations were performed to study the structure of experimentally inaccessible =82 isotones below Sn. The results evidence a surprising absence of proton subshell closures along the chain of =82 isotones. This finding bears consequences on the evolution of the =82 shell gap along the r-process path.