The Decay Process: An Exactly Soluble Example and its Implications

  • Gaston García-Calderón
  • Gerardo Loyola
  • Marcos Moshinsky


There is agreement on the exponential decay law for unstable states in a certain range of times but not on what happens for very long or very short times. In particular for the latter a paradox appears from the contradictory results of two very straightforward calculations. To understand the matter better we consider s-states limited by a δ function radial potential of infinite height at a distance r = a. At time t = 0 we lower the height of the δ toa finite value b and obtain in an explicit analytic form the decay amplitude as a function of time in the full interval 0 ≤ t ≤ ∞. Our results support one of the calculations for very short times based on a schematic theory of nuclear reactions.


Nuclear Reaction Half Plane Decay Amplitude Compound Particle Delta Potential 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1992

Authors and Affiliations

  • Gaston García-Calderón
  • Gerardo Loyola
    • 1
  • Marcos Moshinsky
    • 2
  1. 1.Instituto de FísicaUNAMMéxico
  2. 2.El Colegio NacionalMéxico

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