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引言 理论计算指出:超越周期表末端存在一个以Z=114,N=184为中心的相当稳定的超重核岛,岛上的一些核素可能有相当长的半衰期。若把超重区(106—116)中各核素的三种衰变方式一起考虑,发现~(294)110是最佳候选者,它具有10~8年的总半寿命。 由于测量源厚度的限制以及为了提高探测灵敏度,测量前必须对样品进行化学浓集。观察与天然核素发射的(能量已知的)α粒子不同的α事件或自发裂变事件,是判断超重核存在的一种很灵敏的方法。
INTRODUCTION Theoretical calculations show that there is a rather stable overweight nuclear island beyond the end of the periodic table centered around Z = 114 and N = 184. Some of the islands may have quite long half lives. Considering the three decay patterns of all the nuclides in the overweight region (106-116) together, we found that ~ (294) 110 is the best candidate with a total half-life of 10-8 years. Due to the limitations of the thickness of the measurement source and to increase the detection sensitivity, the sample must be chemically concentrated prior to measurement. Observing α-events or spontaneous fission events that are different from α-particles of known (energetic) energy emitted by natural radionuclides is a very sensitive method of determining the presence of a super-heavy nucleus.