Open Access

Volker Werner, C. Santamaria, C. Louchart, Alexandre Obertelli, Pieter Doornenbal, Frédéric Nowacki, Gilles Authelet, Hidetada Baba, Denis Calvet, F. Château, Anna Corsi, Alain Delbart, Jean-Marc Gheller, Alain Gillibert, Tadaaki Isobe, Valérie Lapoux, M. Matsushita, S. Momiyama, Tohru Motobayashi, Megumi Niikura, Hideaki Otsu, Cedric Péron, Alan Peyaud, Emanuel C. Pollacco, Jean-Yves Andre Roussé, Hiroyoshi Sakurai, Masaki Sasano, Y. Shiga, Satoshi Takeuchi, Ryo Taniuchi, Tomohiro Uesaka, Haohao Wang, Ken-ichiro Yoneda, Frank Browne, L.X. Chung, Zsolt Dombrádi, Serge Franchoo, F. Giacoppo, A. Gottardo, Katarzyna Hadyńska-Kęk, Zeren Korkulu, Shunpei Koyama, Yuichi Kubota, J. Lee, Marc Lettmann, R. Lozeva, K. Matsui, T. Miyazaki, Shunji Nishimura, L. Olivier, S. Ota, Z. Patel, Norbert Pietralla, E. Sahin, C. Shand, Pär-Anders Söderström, I. Stefan, David Steppenbeck, Toshiyuki Sumikama, Daisuke Suzuki, Zs. Vajta, J. Wu, Z. Xu

• Within the SEASTAR project at RIKEN-RIBF, 66Cr and 70,72Fe have been produced via protonknockout reactions, and their first excited 2+ and 4+ states have been discovered. The combination of the liquid-hydrogen target and TPC system MINOS has been used in combination with the DALI2 detector array for the first time. A 345 MeV/u 238U beam with a mean intensity of about 12 pnA impinged on a Be target. Fission fragments were separated and identified using the BigRIPS spectrograph, and reaction products were analyzed using the ZeroDegree spectrograph. A plateau of excitation energies, with a small change in the systematic trends past N = 44, reveals an extension of the N = 40 region of collectivity toward N = 50. Hence, the isotopes of interest are located within the N = 40 island of inversion. An interpretation of the observed trends is offered through large scale shell model calculations.