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用重离子(如Kr、Xe、U)去轰击重靶(如U),然后用化学方法分离反应产物,通过测定γ射线可以从反应产物的质量分布研究反应机制并鉴定反应产物,从而寻找超重元素。两个很重的原子核碰撞(如Kr+U、Xe+U、U+U等),从反应机制来分有下列三类: 1.准弹性转移:当重离子的能量比较低时,两个重离子作擦边碰撞。同时有少数几个核子转移。当入射粒子及靶都比较重时,转移反应形成的残核有较大的机率发生裂变,给出的裂变产物的质量分布是双峰的。 2.全熔合:当两个重原子核碰撞,且能量很大时,可以形成一个大的原子核。熔合成的新核通常有很高的激发能。可以通过发射中子或裂变使原子核达到基态,这时,可能得到很重的原子核,即超重元素。
Heavy targets (such as Kr, Xe, U) are bombarded with heavy targets (such as U), and then the reaction products are chemically separated. The reaction mechanism can be studied from the mass distribution of the reaction products by measuring γ-rays and the reaction products can be identified to find overweight element. Two heavy nuclear collisions (such as Kr + U, Xe + U, U + U, etc.), from the reaction mechanism is divided into the following three categories: 1. Quasi-elastic transfer: When the heavy ion energy is relatively low, the two Heavy ions for scratching the collision. There are also a few nuclear transfers at the same time. When the incident particles and targets are relatively heavy, the residual nuclei formed by the transfer reaction have a greater probability of fission, and the mass distribution of the fission products given is bimodal. 2. Fully fused: When two heavy nuclei collide, and the energy is very large, you can form a large nucleus. New fusion nuclei usually have a high excitation energy. By launching neutrons or fission to the nucleus to the ground state, then, may get heavy nuclei, that is, overweight elements.