Direct mass measurements of neutron-rich 86Kr projectile fragments and the persistence of neutron magic number N=32 in Sc isotopesSupported by 973 Program of China (2013CB834401), the NSFC (U1232208, U1432125, 11205205, 11035007) and the Helmholtz-CAS Joint Research Group (HCJRG-108)

• Published in: Chinese physics C 2015-10, Vol.39 (10)
• Main Authors: Xu, Xing, Wang, Meng, Zhang, Yu-Hu, Xu, Hu-Shan, Shuai, Peng, Tu, Xiao-Lin, Litvinov, Yuri A., Zhou, Xiao-Hong, Sun, Bao-Hua, Yuan, You-Jin, Xia, Jia-Wen, Yang, Jian-Cheng, Blaum, Klaus, Chen, Rui-Jiu, Chen, Xiang-Cheng, Fu, Chao-Yi, Ge, Zhuang, Hu, Zheng-Guo, Huang, Wen-Jia, Liu, Da-Wei, Lam, Yi-Hua, Ma, Xin-Wen, Mao, Rui-Shi, Uesaka, T., Xiao, Guo-Qing, Xing, Yuan-Ming, Yamaguchi, T., Yamaguchi, Y., Zeng, Qi, Yan, Xin-Liang, Zhao, Hong-Wei, Zhao, Tie-Cheng, Zhang, Wei, Zhan, Wen-Long
• Format: Article
• Language: English
• Subjects: exotic nuclei; isochronous mass spectrometry; mass excess; new magic number
• ISSN: 1674-1137
• DOI: 10.1088/1674-1137/39/10/104001

In this paper, we present direct mass measurements of neutron-rich 86Kr projectile fragments conducted at the HIRFL-CSR facility in Lanzhou by employing the Isochronous Mass Spectrometry (IMS) method. The new mass excesses of 52-54Sc nuclides are determined to be −40492(82), −38928(114), −34654(540) keV, which show a significant increase of binding energy compared to the reported ones in the Atomic Mass Evaluation 2012 (AME12). In particular, 53Sc and 54Sc are more bound by 0.8 MeV and 1.0 MeV, respectively. The behavior of the two neutron separation energy with neutron numbers indicates a strong sub-shell closure at neutron number N=32 in Sc isotopes.