Tests of CPT invariance for neutral-flavoured-meson--antimeson mixing

Abstract

We focus on two aspects of CPT invariance in neutral-meson--antimeson ($M^0{\bar{M}}^0$) mixing: 1. Tests of CPT invariance, using only the property of ``lack of vacuum regeneration'', which occurs as a part of the well-known Lee--Oehme--Yang (LOY) theory; 2. Methods for extracting the CPT-violating mixing parameter $\theta$ through explicit calculations by using the LOY-type theory fully. In the latter context, we demonstrate the importance of the C-even $|M^0{\bar{M}}^0>$ state. In particular, by measuring the time dependence of opposite-sign dilepton events arising from decays of the C-even and C-odd $|M^0{\bar{M}}^0>$ states, $\theta$ may be disentangled from the parameters ${\lambda }_{+}$ and ${\bar{\lambda }}_{-}$ characterizing violations of the $\Delta F=\Delta Q$ rule. Furthermore, these two parameters may also be determined. The same is true if one uses like-sign dilepton events arising from only the C-even $|M^0{\bar{M}}^0>$ state.

Comments: 13 pages, no figures, Revtex; change in title, extensive changes in the presentation, version to be published in Eur. Phys. J. C