Alpha decay tunneling

The principle of small nuclear changes was given a theoretical basis by George Gamow. In 1928 he derived a successful theory of alpha decay, in which the nucleus is quantized and only small particles, such as protons or alpha particles, have a finite probability of tunneling through the nuclear barrier and escaping the nucleus. That... 

FIGURE 10.9 Due to the noninfinite height and depth of the potential energy barrier, the wavefunction has a nonzero probability of existing on the other side of the barrier. Alpha particle decay and small gaps between two surfaces are two systems where tunneling occurs. 

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