Discovery of New Isotopes Os160 and W156 : Revealing Enhanced Stability of the N=82 Shell Closure on the Neutron-Deficient Side

• DOI: 10.1103/physrevlett.132.072502
• Publication Date: 2024-02-15T15:05:40Z
• Authors: H. B. Yang; Z. G. Gan; Y. J. Li; M. L. Liu; S. Y. Xu; C. Liu; M. M. Zhang; Z. Y. Zhang; M. H. Huang; C. X. Yuan; S. Y. Wang; L. Ma; J. G. Wang; X. C. Han; A. Rohilla; S. Q. Zuo; X. Xiao; X. B. Zhang; L. Zhu; Z. F. Yue; Y. L. Tian; Y. S. Wang; C. L. Yang; Z. Zhao; X. Y. Huang; Z. C. Li; L. C. Sun; J. Y. Wang; H. R. Yang; Z. W. Lu; W. Q. Yang; X. H. Zhou; W. X. Huang; N. Wang; S. G. Zhou; Z. Z. Ren; H. S. Xu

Using the fusion-evaporation reaction ^{106}Cd(^{58}Ni,4n)^{160}Os and gas-filled recoil separator SHANS, two new isotopes _{76}^{160}Os _{74}^{156}W have been identified. The α decay of ^{160}Os, measured with an α-particle energy 7080(26) keV a half-life 201_{-37}^{+58} μs, is assigned to originate from ground state. daughter nucleus ^{156}W β^{+} emitter 291_{-61}^{+86} ms. newly α-decay data allow us derive reduced widths (δ^{2}) for N=84 isotones up osmium (Z=76), which are found decrease increasing atomic number above Z=68. reduction δ^{2} interpreted as evidence strengthening N=82 shell closure toward proton drip line, supported by increase neutron-shell gaps predicted in theoretical models.