Abstract

Spontaneous fissions of the ²⁵²No and ²⁵⁴No nobelium isotopes have been studied in a series of experiments with the SHELS separator. These isotopes are produced by colliding a beam of ⁴⁸Ca ions from the U-400 cyclotron with the ²⁰⁶Pb and ²⁰⁸Pb targets. The measured characteristics of the ²⁵²No and ²⁵⁴No spontaneous fissions include their half-lives, total kinetic energies of fission fragments, and prompt-neutron multiplicities. The average number of neutrons per ²⁵⁴No spontaneous-fission act is measured for the first time as 4.88 ± 0.53.

中文翻译：

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252No和254No同位素自发裂变特性对比研究

摘要

在使用 SHELS 分离器进行的一系列实验中，研究了²⁵² No 和²⁵⁴ No 同位素的自发裂变。这些同位素是通过来自 U-400 回旋加速器的^{48 个}Ca 离子束与²⁰⁶ Pb 和²⁰⁸ Pb 目标碰撞而产生的。²⁵² No 和²⁵⁴ No 自发裂变的测量特征包括它们的半衰期、裂变碎片的总动能和瞬发中子多重性。首次测得的每^{254 个}无自发裂变行为的平均中子数为 4.88 ± 0.53。