NSCL/ Michigan State University
FUSTIPEN, Caen
May 28, 2014

* [Kubo] - exponential decay corresponds to the condition for a physical process to be approximated as a Markovian process
* [Silverman] - indeed a random process, no “cosmic force”
* [Merzbacher] - result of “delicate” approximations
Three stages : short-time main (exponential) Oscillations?
long-time

Why and when decay cannot be exponential
Initial state “memory” time
Internal motion in quasi-bound state
Remote power-law
There are “free” slow-moving non-resonant particles, they escape slowly
Example 14 C decay: E
0
=0.157 MeV t
2
=10 -21 s
=73
6

Time dependence of decay, Winter’s model
Winter, Phys. Rev., 123,1503 1961.
7

Winter’s model:
Dynamics at remote times background
8

Scattering cross section off a single resonance near threshold and survival probability
Radiating state and parameters of the time dependence of its wave function

Internal dynamics in decaying system
Winter’s model t
2 t
1
1
0

Is it possible to have oscillatory decay?
Current
Decay oscillations are possible
• Kinetic energy - mass eigenstates
• Interaction (barrier)- flavor eigenstates
• Fast and slow decaying modes
Survival probability
[1] A Volya, M. Peshkin, and V. Zelevinsky, work in progress