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Modern Physics Letters A

FLAVOR AND CHIRAL OSCILLATIONS

Alex E. Bernardini, Stefano De Leo

Published Mar 21, 2005• 7 citations

Abstract

We seek a quantum-theoretic expression for the probability that a "fermionic" particle which is initially in a well-defined flavor, linear combination of mass-eigenstates, will be found, at later times, in another flavor state. We approach this problem by using the Dirac equation as evolution equation for the mass-eigenstates. The Dirac formalism is useful and essential in keeping clear many of the conceptual aspects of quantum oscillation phenomena that naturally arise in a relativistic spin one-half particle theory. Our study leads to the conclusion that the fermionic nature of the particles and the interference between positive and negative frequency components of mass-eigenstate wave packets modify the standard oscillation probability, obtained by implicitly assuming a "scalar" nature of the mass-eigenstates. Nevertheless, under particular assumptions, i.e. ultra-relativistic particles, strictly peaked momentum distributions and minimal slippage, these modifications introduce correction factors proportional to [Formula: see text] which are practically un-detectable by any experimental analysis.

DOI: 10.1142/s0217732305016130

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