Isomeric states observed in heavy neutron-rich nuclei populated in the fragmentation of a Pb beam

Pbビームの破砕反応で生成された中性子過剰重原子核の核異性体準位

Steer, S. J.*; Podolyk, Z.*; Pietri, S.*; Grska, M.*; Grawe, H.*; Maier, K.*; Regan, P. H.*; Rudolph, D.*; Garnsworthy, A. B.*; Hoischen, R.*; Gerl, J.*; Wollersheim, H. J.*; Becker, F.*; Bednarczyk, P.*; Cceres, L.*; Doornenbal, P.*; Geissel, H.*; Grbosz, J.*; Kelic, A.*; Kojouharov, I.*; Kurz, N.*; Montes, F.*; Prokopowicz, W.*; 齊藤 武彦*; Schaffner, H.*; Tashenov, S.*; Heinz, S.*; Pftzner, M.*; Kurtukian-Nieto, T.*; Benzoni, G.*; Jungclaus, A.*; Balabanski, D. L.*; Bowry, M.*; Brandau, C.*; Brown, B. A.*; Bruce, A. M.*; Catford, W. N.*; Cullen, I. J.*; Dombrdi, Zs.*; Estevez, M. E.*; Gelletly, W.*; Ilie, G.*; Jolie, J.*; Jones, G. A.*; Kmiecik, M.*; Kondev, F. G.*; Krcken, R.*; Lalkovski, S.*; Liu, Z.*; Maj, A.*; Myalski, S.*; Schwertel, S.*; 静間 俊行; Walker, P. M.*; Werner-Malento, E.*; Wieland, O.*

Steer, S. J.*; Podolyk, Z.*; Pietri, S.*; Grska, M.*; Grawe, H.*; Maier, K.*; Regan, P. H.*; Rudolph, D.*; Garnsworthy, A. B.*; Hoischen, R.*; Gerl, J.*; Wollersheim, H. J.*; Becker, F.*; Bednarczyk, P.*; Cceres, L.*; Doornenbal, P.*; Geissel, H.*; Grbosz, J.*; Kelic, A.*; Kojouharov, I.*; Kurz, N.*; Montes, F.*; Prokopowicz, W.*; Saito, Takehiko*; Schaffner, H.*; Tashenov, S.*; Heinz, S.*; Pftzner, M.*; Kurtukian-Nieto, T.*; Benzoni, G.*; Jungclaus, A.*; Balabanski, D. L.*; Bowry, M.*; Brandau, C.*; Brown, B. A.*; Bruce, A. M.*; Catford, W. N.*; Cullen, I. J.*; Dombrdi, Zs.*; Estevez, M. E.*; Gelletly, W.*; Ilie, G.*; Jolie, J.*; Jones, G. A.*; Kmiecik, M.*; Kondev, F. G.*; Krcken, R.*; Lalkovski, S.*; Liu, Z.*; Maj, A.*; Myalski, S.*; Schwertel, S.*; Shizuma, Toshiyuki; Walker, P. M.*; Werner-Malento, E.*; Wieland, O.*

核子あたり1GeVのPbを用いて核破砕反応により中性子過剰重原子核を生成した。反跳質量分析法により破砕核を分離し、核種を同定した。核異性体から放出される遅延線の測定により、49核異性体の検出に成功した。殻模型やBCS計算を用いて、これらの核異性体の準位構造を明らかにした。

Heavy neutron-rich nuclei were populated via the fragmentation of a E/A=1 GeV Pb beam. Secondary fragments were separated and identified and subsequently implanted in a passive stopper. By the detection of delayed rays, isomeric decays associated with these nuclei have been identified. A total of 49 isomers were detected, with the majority of them observed for the first time. Possible level schemes are constructed and the structure of the nuclei discussed. To aid the interpretation, shell-model as well as BCS calculations were performed.