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

TL;DR

This paper re-examines the contribution of the non-manifest Left-Right Symmetric Model to the lifetime difference in $D^0 - ar{D}^0$ mixing, finding it negligible due to GIM cancellation.

Contribution

It demonstrates that the dominant diagrams with $W_L - W_R$ mixing are negligible, challenging previous assumptions about their significance in this context.

Findings

Left-Right Model contribution is about two orders of magnitude less than experimental data.

GIM cancellation renders certain diagrams negligible in the mixing process.

Re-evaluation of the model's impact on $D^0 - ar{D}^0$ 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 $\Delta \Gamma_D$.