PowerPoint Presentation

Do we understand Quantum Decay? Vladimir Zelevinsky NSCL/ Michigan State University FUSTIPEN, Caen May 28, 2014Quantum Decay: exponential versus non-exponential * [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 approximationsThree stages: short-time main (exponential) Oscillations? long-time

Quantum mechanics of decay4

Why exponential decay? Survival amplitude and probabilityResonance wave functionTime evolution and decay in quantum mechanics

EDiscussion continues: Is radioactive decay exponential?5The GSI oscillations Mystery (2008)Periodic modulation of the expected exponential law in EC-decays of different highly charged ions Litvinov et al. Phys. Lett. B 664, 162 (2008);P. Kienle et al. Phys. Lett. B 726, 638 (2013).

Half life 5,730 40 years mean-life time 8,033 yearsCarbon dating and non-exponential decay (2012)If the decay of 14C is indeed non-exponential... this would remove a foundation stone of modern dating methods." Aston EPL 97, 52001 (2012).

Period = 7 sec !Why and when decay cannot be exponential6Initial state memory time

Internal motion in quasi-bound state

Remote power-law

There are free slow-moving non-resonant particles, they escape slowly

Example 14C decay: E0=0.157 MeV t2=10-21 s

=73

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Time dependence of decay, Winters modelWinter, Phys. Rev., 123,1503 1961.

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Winters model: Dynamics at remote times

backgroundresonanceProbability distributionScattering cross sectionoff a single resonance near threshold and survival probability

Radiating state and parameters of the timedependence of its wave functionInternal dynamics in decaying system Winters model10

t2t1

Is it possible to have oscillatory decay?[1] A Volya, M. Peshkin, and V. Zelevinsky, work in progress

Decay oscillations are possibleKinetic energy - mass eigenstatesInteraction (barrier)- flavor eigenstatesFast and slow decaying modesoscillationsCurrentSurvival probability