Search for the Rare Decays J/Psi --> Ds- e+ nu_e, J/Psi --> D- e+ nu_e, and J/Psi --> D0bar e+ e-

TL;DR

This study searched for rare J/Psi decays into specific charm mesons with electrons and neutrinos, setting upper limits on their branching fractions due to no observed signal.

Contribution

First search for these rare J/Psi decay modes, establishing upper limits on their branching fractions with a large data sample.

Findings

No significant signal observed for the decay modes.

Upper limits on branching fractions were set at 4.8×10^-5, 1.2×10^-5, and 1.1×10^-5.

Results constrain theoretical models of rare charm decays.

Abstract

We report on a search for the decays J/Psi --> Ds- e+ nu_e + c.c., J/Psi --> D- e+ nu_e + c.c., and J/Psi --> D0bar e+ e- + c.c. in a sample of 5.8 * 10^7 J/Psi events collected with the BESII detector at the BEPC. No excess of signal above background is observed, and 90% confidence level upper limits on the branching fractions are set: B(J/Psi --> Ds- e+ nu_e + c.c.)<4.8*10^-5, B(J/Psi --> D- e+ nu_e + c.c.)<1.2*10^-5, and B(J/Psi --> D0bar e+ e- + c.c.)<1.1*10^-5