On the Non-Manifest Left-Right Model Contribution to the Lifetime Difference in $D^0 - \bar{D}^0$ Mixing

Abstract

New physics contribution to the lifetime difference in $D^0 - \bar{D}^0$ mixing is re-examined within the non-manifest Left-Right Symmetric Model. Diagrams with one of $\Delta C = 1$ transitions, mediated by a propagator with $W_L - W_R$ mixing, are revisited. While these diagrams are believed to give the dominant contribution, compatible with the experimental data, it is shown that due to GIM cancelation, such diagrams are negligible in sum. Thus, Left-Right Symmetric Model contribution to the lifetime difference in $D^0 - \bar{D}^0$ mixing is about two orders of magnitude less than actual experimental value for $\Delta \Gamma_D$.