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通过重离子熔合蒸发反应~(180)W(~(40)Ar,xn)~(220-x)U,合成了两个缺中子新核素~(216)U和~(215)U.目标核由熔合反应产生后从薄靶中反冲出来,在飞行中被兰州充气谱仪从大量的本底离子中分离并偏转到探测系统.探测系统对目标核的注入以及随后将发生的α衰变进行探测.探测器上产生的信号经电子学处理后被数据获取系统转换成一定格式的数据保存下来.实验采用能量-位置-时间关联的数据分析方法来寻找和鉴别目标核.在束流能量为187.2 MeV的情况下,新核素~(216)U的两个α衰变态被观察到:一是基态,它的α粒子能量为10.384(30)MeV,半衰期为4.72_(-1.57)~(+4.72)ms;二是自旋宇称为8~+的同核异能素态,它的α粒子能量为10.582(30)MeV和8.182(30)MeV,半衰期为1.31_(-0.48)~(+1.80)ms.在束流能量为205.5 MeV的情况下,新核素~(215)U被观测到,它的α粒子能量和半衰期被确定为8.428(30)MeV和0.73_(-0.29)~(+1.33)ms.此外,实验还观测到从~(217)U的基态产生的两个新的α跃迁,它们的α粒子能量分别为8.210(30)MeV和8.098(30)Mev.
Two new neutron-deficient nuclei ~ (216) U and ~ (215) U were synthesized by heavy ion fusion reaction ~ (180) W (~ (40) Ar, xn) ~ (220-x) U. The target nucleus is recoiled from the thin target by the fusion reaction and is separated from the bulk of the background ions by the Lanzhou gas chromatograph in flight and deflected to the detection system. The detection system injects the target nucleus and the α Decay is detected.The signals generated on the detector are electronically processed and then converted to data formatted by the data acquisition system.The experiment uses energy-position-time-related data analysis methods to find and identify the target nuclei.At the same time, At the energy of 187.2 MeV, two α decay states of ~ (216) U are observed: one is the ground state, the α particle energy is 10.384 (30) MeV and the half-life is 4.72 _ (-1.57) ~ (+4.72) ms. The other is the isonuclear isotope with 8 ~ +, whose alpha particle energies are 10.582 (30) MeV and 8.182 (30) MeV with a half-life of 1.31 ) ~ (+1.80) ms. At a beam energy of 205.5 MeV, ~ (215) U was observed and its alpha particle energy and half-life were determined to be 8.428 (30) MeV and 0.73 -0.29) to (+1.33) ms In addition, two new α transitions from the ground state of (217) U were also observed. Their α-particle energies were 8.210 (30) MeV and 8.098 (30) Mev, respectively.