Implications of D^0-\bar D^0 Mixing for New Physics

TL;DR

This paper analyzes how potential New Physics could influence D0-D0bar mixing, using effective Hamiltonians and exploring various models, with recent experimental data constraining these theories.

Contribution

It provides a comprehensive analysis of New Physics contributions to D0-D0bar mixing, including model constraints and comparison with experimental results.

Findings

Strong constraints on New Physics models surpassing other search methods

Recent experimental evidence limits parameter space of New Physics scenarios

Review of Standard Model predictions and recent experimental findings

Abstract

We provide a comprehensive, up-to-date analysis of possible New Physics contributions to the mass difference $\Delta M_D$ in $D^0$-${\bar D}^0$ mixing. We consider the most general low energy effective Hamiltonian and include leading order QCD running of effective operators. We then explore an extensive list of possible New Physics models that can generate these operators, which we organize as including Extra Fermions, Extra Gauge Bosons, Extra Scalars, Extra Space Dimensions and Extra Symmetries. For each model we place restrictions on the allowed parameter space using the recent evidence for observation of $D$ meson mixing. In many scenarios, we find strong constraints that surpass those from other search techniques and provide an important test of flavor changing neutral currents in the up-quark sector. We also review the recent BaBar and Belle findings, and describe the current status of the Standard Model predictions of $D^0$-${\bar D}^0$ mixing.