Nuclear Physics C. Nuclear Dynamics, Experimental
Nuclear Physics C. Nuclear Dynamics, Experimental
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DOI：
10.1103/revmodphys.9.245
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发表时间：
1937-07
影响因子：
44.1
通讯作者：
M. Livingston;H. Bethe
中科院分区：
文献类型：
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作者：
M. Livingston;H. Bethe
卢瑟福于1919年首次用Ra C '的高速α粒子作为抛射体完成了元素的人工衰变，比其他抛射体早了100多年。到1930年，几个实验室都在致力于研制高压仪器，以人工产生高速离子。人们预计，需要足够的能量来穿透原子核的力场，即几百万伏，而质子被认为是最有可能成为抛射体的粒子。在这个阶段，伽莫夫（Gamow）（* 7）和康登（Condon）和格尼（Gurney）（C32）介绍了自然Q的量子力学解释。一种衰变，根据这种衰变，能量比越过势垒顶部所需能量小得多的粒子穿透势垒的概率是一定的。Cock-croft和Walton（C18）意识到这可能使相对低能量的质子衰变成为可能，并进行了第一次成功的实验，导致了Li的衰变。'19）。劳伦斯、利文斯顿和白色（L11）立即用磁共振加速器提供的1 MV质子检查了这些观测结果，其他人很快跟进，有些人使用了低得多的质子能量，证明了假设的有效性。目前，
Artificial disintegration of elements was hrst accomplished by Rutherford in 1919 using the high speed alpha-particles from Ra C'as pro-jectiles, and more than 10yearspassed before any other projectiles were considered. By 1930several laboratories were working on the development of high voltageapparatus to produce high speed ions artificially. It was expected that energies sufficient to penetrate the force fields of nuclei would be required, ie, several million volts, and the proton was considered the most likely p~ ssibility as a projectile. At this stage Gamow ('(* 7) and Condon and Gurney (C32) introduced the quantum mechanical interpretation of natural Q.-decay according to which thereexists a certain probability of penetration of a potential barrier by particles with considerably less energy than required to go over the top of the barrier. Cock-croft and Walton (C18) realized that this might make disintegrations possible with relatively low energy protons and performed the first successful experiment resulting in the disintegration of Li ((.'19). Lawrence, Livingston and White (L11) immediately checked these observations with the 1 MV protons then available with the magnetic resonance accelerator, and others soon followed, some using much lower proton energies and proving the validity of the hypothesis. At the present time the projectiles that have