Gamow—Condon—Gurney formula

The theoretical Gamow-Condon-Gurney formula (O Eq. (2.65), Ghap. 2) describes the alpha decay constant as a function of the alpha-energy (or rather the Q-value of the alpha decay), as well as the nuclear radius and the atomic number of the daughter. 

The Gamow-Condon-Gurney formula only applies when the alpha particle is emitted with zero angular momentum. The probability for alpha decay taking away angular momentum is considerably smaller (see Eq. (2.68) and Table 2.8 in Ghap. 2). 

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