Search for X(3872) in Untagged gamma gamma Fusion and Initial State Radiation Production with CLEO III

TL;DR

This study searches for the X(3872) particle in gamma-gamma fusion and initial state radiation processes using CLEO III data, setting upper limits on its production rates due to no observed signals.

Contribution

First to perform an exclusive search for X(3872) in these production modes with CLEO III, establishing upper limits on its gamma-gamma and e+e- production rates.

Findings

No signals observed for X(3872) in the studied channels.

Established upper limits on production rates at 90% confidence level.

Abstract

We report on an exclusive search for the X(3872) state in the decay pi+ pi- J/psi, J/psi to l+ l- (l = e, mu) from untagged gamma-gamma fusion and initial state radiation production using a 15.1 fb-1 data sample with the CLEO III detector. By taking advantage of the unique pi+ pi- J/psi decay kinematics, separate measurements for each production process are obtained. No signals are observed and preliminary upper limits have been established as [(2J+1)*Width_gamgam(X(3872))*BR(X(3872) to pi+ pi- J/psi)] < 12.9 eV and [Width_ee(X(3872))*BR(X(3872) to pi+ pi- J/psi)] < 8.0 eV, both at a 90% confidence level.