Alpha decay properties of the semi-magic nucleus 219Np

2018 update of the discoveries of nuclides

“…The first identification of 219 Np was reported by Yang et al in the paper "Alpha decay properties of the semi-magic nucleus 219 Np". 13 A 191.5 MeV 36 Ar was accelerated with the Sector Focusing Cyclotron of the heavy ion research facility in Lanzhou (HIRFL), China. Residues from the fusion-evaporation reaction 187 Re( 36 Ar,4n) were identified with the gas-filled recoil separator SHANS.…”

基于神经网络预测重核α衰变半衰期

“…, [214][215][216]221 U [3,[6][7][8], 219,220,222−224 Np [1,2,[9][10][11], 220,221 Pa [12,13], 236 Bk [14], 240 Es [14], 和 224 Md [15]. 在这些研究中，α衰变是一 种重要手段，通过对α衰变的研究，可以得到原子 核的基态半衰期，结合能, 壳结构信息，是重核合 成的重要鉴别手段。 对 α 衰 变 的 理 论 研 究 始 于19世 纪， Gamow [16]， Gurney [17] [24][25][26][27][28][29][30][31][32]，多道团簇模型(MCCM) [33,34]， 通用衰变律(GLDM) [35,36]，四次波函数方法 [37,38]，以及四因子模型 [39]。一些经验公式 [40][41][42] [40,41]。从已有的经验公式中，α衰变的Q值,原 子核的质子数和质量数Z，A被用来计算半衰期， 半衰期与Q值成负相关，与Z和A成正相关。我们对 源数据作如下处理:…”

New α -Emitting Isotope U214 and Abnormal Enhancement of <

“…However, at most four decay chains from the ground state of 216 U were observed in each study, resulting in a relatively large uncertainty of decay half-life. In the present investigation, the same experimental setup as for 214 U was used, but with a reaction of 180 W( 40 [44,[47][48][49] (see Table I).…”

“…A new α-emitting isotope 214 U, produced by fusion-evaporation reaction 182 W( 36 Ar, 4n) 214 U, was identified by employing the gas-filled recoil separator SHANS and recoil-α correlation technique. More precise α-decay properties of even-even nuclei 216,218 U were also measured in reactions of 40 Ar, 40 Ca with 180,182,184 W targets. By combining the experimental data, improved α-decay reduced widths δ 2 for the even-even Po-Pu nuclei in the vicinity of magic neutron number N = 126 were deduced.…”