Speaker
Description
The KEK Wako Nuclear Science Center (WNSC) has developed the KEK Isotope Separation System (KISS) [1] at RIKEN to study the nuclear structure of the nuclei in the vicinity of neutron magic number N = 126, trans-uranium elements, and actinides. This research aims to explore the origin of heavy elements synthesized by the rapid neutron capture process. These neutron-rich nuclei have been produced by using multinucleon transfer (MNT) reactions [2] with the combinations of the low-energy $^{136}$Xe/$^{238}$U beams and the production targets of W, Ir, and Pt. At the KISS facility, these radioisotopes are ionized by applying in-gas-cell resonant laser ionization technique. Their nuclear spectroscopy, including decay studies at a beta-gamma decay station [3], precise mass measurements using MRTOF-MS [4], and laser spectroscopy [5] have been successfully performed.
To further conduct this research, WNSC have recently started the construction of KISS-1.5 [6], which will provide much higher yields of MNT products for nuclear spectroscopy.
In the talk, we will introduce the KISS facility, report the recent experimental results, and discuss future perspectives at KISS-1.5.
References
[1] Y. Hirayama et al., Nucl. Inst. Meth. B353, 4 (2015), and B412, 11 (2017).
[2] Y.X. Watanabe et al., Phys. Rev. Lett. 172503, 1 (2015).
[3] M. Mukai et al., Nucl. Inst. Meth. A884, 1 (2018), Y. Hirayama et al., NIMA997, 165152 (2021).
[4] P. Schury et al., Nucl. Inst. Meth. B317, 537 (2013).
[5] Y. Hirayama et al., PRC96(2017)014307, PRC106(2022)034326, M. Mukai et al., PRC(2020)054307, and H. Choi et al., PRC102(2020)034309.
[6] Design report of the KISS-II facility for exploring the origin of uranium, arXiv:2209.12649.
