psi’ update

September 14, 2006

Sometime around last Monday, CLEO-c accumulated the world’s largest sample of ψ(3686) decays produced on-resonance. This dataset will be used primarily for studies of how the strong force binds charm-anticharm systems and how transitions between these states occur. There’s also interest in exploring light mesons (those made entirely of u, d, and s quarks) that are produced in the aftermath of charm-anticharm annihilation. This dataset also turns out to be amazingly useful for calibration purposes, because of the numerous clean and well-constrained decays like ψ(3686) → J/ψ π+ π → μ+ μ π+ π which serve as “standard candles,” to appropriate an astronomy term.