Weisskopf-Wigner model

Two decades after the exponential decay theories of Gamow, and Weisskopf and Wigner, Hellund [52] showed that decay could not be exactly exponential and that it should be slower at long times. Later on, Hohler, going beyond the simplifications of the Weisskopf-Wigner model, obtained a power law for long times [53] see also Ref. [54]. 

The giant resonance interpretation of the nucleon-nucleus interaction of Lane, Thomas, and Wigner [77]. Following the rough success of the Feshbach, Porter, and Weisskopf optical model match to the average cross sections over... 

The natural line width was first derived from a classical radiation damping model and was later derived on a quantum mechanical basis by Weisskopf and Wigner and Hoyt. It is due to uncertainty in the energy of the excited level having a finite lifetime. The natural line width is much smaller than will be of concern in this paper, of the order of 0.01 cm. ... 

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