Synthesis of the isotopes of elements 118 and 116 in the {sup 249}Cf and {sup 245}Cm+{sup 48}Ca fusion reactions
Synthesis of the isotopes of elements 118 and 116 in the {sup 249}Cf and {sup 245}Cm+{sup 48}Ca fusion reactions
复制标题
DOI：
10.1103/physrevc.74.044602
复制
发表时间：
2006-10
影响因子：
3.1
通讯作者：
Y. Oganessian;V. Utyonkov;Y. Lobanov;F. Abdullin;A. Polyakov;R. Sagaidak;I. V. Shirokovsky;Y. Tsyganov
中科院分区：
文献类型：
--
作者：
Y. Oganessian;V. Utyonkov;Y. Lobanov;F. Abdullin;A. Polyakov;R. Sagaidak;I. V. Shirokovsky;Y. Tsyganov
{sup 290}116 和 {sup 291}116 的衰变特性，以及它们的产生截面对复合核 {sup 293}116 激发能的依赖性，已在 {sup 245}Cm ({sup 48}Ca, xn){sup 293-x}116 反应中测量。 116 号元素的这些同位素是 118 号元素同位素的衰变子体，它们是通过 {sup 249}Cf+{sup 48}Ca 反应产生的。我们在两种射弹能量下进行了 118 号元素实验，对应于 E*=29.2{+-}2.5 和 34.4{+-}2.3 MeV 的 {sup 297}118 复合核激发能。在总束剂量为 4.1x10{sup 19} {sup 48}Ca 射弹的照射过程中，观察到三个相似的衰变链，由两个或三个连续的 {α} 衰变组成，并由具有约 230 MeV 高总动能的自发裂变 (SF) 终止。三个衰变链源自{sup 249}Cf+{sup 48}Ca反应的3n蒸发通道中产生的最大截面的偶偶同位素{sup 294}118 (E{sub {alpha}}=11.65{+-}0.06 MeV, T{sub {alpha}}=0.89{sub -0.31}{sup +1.07} ms) 0.5{sub -0.3}{sup +1.6} pb。
The decay properties of {sup 290}116 and {sup 291}116, and the dependence of their production cross sections on the excitation energies of the compound nucleus, {sup 293}116, have been measured in the {sup 245}Cm ({sup 48}Ca, xn){sup 293-x}116 reaction. These isotopes of element 116 are the decay daughters of element 118 isotopes, which are produced via the {sup 249}Cf+{sup 48}Ca reaction. We performed the element 118 experiment at two projectile energies, corresponding to {sup 297}118 compound nucleus excitation energies of E*=29.2{+-}2.5 and 34.4{+-}2.3 MeV. During an irradiation with a total beam dose of 4.1x10{sup 19} {sup 48}Ca projectiles, three similar decay chains consisting of two or three consecutive {alpha} decays and terminated by a spontaneous fission (SF) with high total kinetic energy of about 230 MeV were observed. The three decay chains originated from the even-even isotope {sup 294}118 (E{sub {alpha}}=11.65{+-}0.06 MeV, T{sub {alpha}}=0.89{sub -0.31}{sup +1.07} ms) produced in the 3n-evaporation channel of the {sup 249}Cf+{sup 48}Ca reaction with a maximum cross section of 0.5{sub -0.3}{sup +1.6} pb.