Eur. Phys. J. C (2007) 49: 721-730
https://doi.org/10.1140/epjc/s10052-006-0138-x

Regular Article - Theoretical Physics

On Khalfin’s improvement of the LOY effective Hamiltonian for neutral meson complex

Institute of Physics, University of Zielona Góra, ul. Prof. Z. Szafrana 4a, 65-516, Zielona Góra, Poland

^* e-mail: K.Urbanowski@proton.if.uz.zgora.pl

Received: 19 March 2006
Revised: 16 August 2006
Published online: 21 November 2006

Abstract

The general properties of the effective Hamiltonian for the neutral meson system improved by Khalfin in 1980 are studied. It is shown that contrary to the standard result of the Lee–Oehme–Yang (LOY) theory, the diagonal matrix elements of this effective Hamiltonian cannot be equal in a CPT invariant system. It is also shown that the scalar product of short, , and long, , living superpositions of neutral kaons cannot be real when CPT symmetry is conserved in the system under consideration, whereas within the LOY theory such a scalar product is real.