Jun 13 – 17, 2011
Europe/Berlin timezone
Proceedings are now available online at <a href="http://www.slac.stanford.edu/econf/C110613/">eConf</a>

Measuring the phase between strong and EM J/psi decay amplitudes

Jun 13, 2011, 4:30 PM
Club 1 (Künstlerhaus)

Club 1


talk Quarkonia Quarkonia


Prof. Marco Maggiora (INFN Torino)


Experimental data in various channels show that in $J/\psi$ decay, strong and electromagnetic amplitudes seem to be orthogonal, while in the standard model they are expected to be both almost real. There has been the conjecture that the phase between strong and electromagnetic amplitudes is universally $-90^\circ$ in all decays of charmonium (quarkonium) $1^{--}$ states. However, so far the determination of this phase has been based mostly on theoretical assumptions about SU(3) symmetry. We propose to measure this phase directly by the scan of the energy region below the charmonium $1^{--}$ resonances. We present the theoretical basis of such measurement and analyze the feasibility and sensitivity for the data to be eventually taken by BES-III experiment.

Primary authors

Dr Ping Wang (IHEP, Beijing) Rinaldo Baldini (LNF, INFN, Italy)

Presentation materials