Flavor Changing Decays of $\Upsilon$ and $J/\psi$

TL;DR

This paper investigates flavor-changing decays of $ $ and $J/\psi$ as potential indicators of new physics beyond the standard model, analyzing their predicted branching ratios in various models.

Contribution

It provides a model-independent analysis and explores predictions of specific new physics models for these rare decay processes.

Findings

Branching ratios could reach up to 10^{-6} and 10^{-5} with new physics.

Standard model predicts these decays to be unobservable.

Potential to detect new physics signals at B and Tau-Charm factories.

Abstract

We study flavor changing processes $\Upsilon \to B/{\bar B} X_s$ and $J/\psi \to D/{\bar D} X_u$ in the B factories and the Tau-Charm factories. In the standard model, these processes are predicted to be unobservable, so they serve as a probe of the new physics. We first perform a model independent analysis, then examine the predictions of models; such as top color models and MSSM with R-parity violation ; for the branching ratios of $\Upsilon \to B/{\bar B} X_s$ and $J/\psi \to D/{\bar D} X_u$ . We find that these branching ratios could be as large as $10^{-6}$ and $10^{-5}$ in the presence of new physics.