Author/Authors :
FOCUS Collaboration، نويسنده , , J.M Link، نويسنده , , M Reyes، نويسنده , , P.M. Yager، نويسنده , , J.C. Anjos، نويسنده , , I Bediaga، نويسنده , , C G?bel، نويسنده , , J Magnin، نويسنده , , A. Massafferri، نويسنده , , J.M de Miranda، نويسنده , , I.M Pepe، نويسنده , , A.C dos Reis، نويسنده , , S Carrillo، نويسنده , , E Casimiro، نويسنده , , E Cuautle، نويسنده , , A S?nchez-Hern?ndez، نويسنده , , C Uribe، نويسنده , , F V?zquez، نويسنده , , L Agostino، نويسنده , , L Cinquini، نويسنده , , et al.، نويسنده ,
Abstract :
Using the FOCUS spectrometer with photon beam energies between 20 and 160 GeV, we confirm the existence of a diffractively photoproduced enhancement in K+K− at 1750 MeV/c2 with nearly 100 times the statistics of previous experiments. Assuming this enhancement to be a single resonance with a Breit–Wigner mass shape, we determine its mass to be 1753.5±1.5±2.3 MeV/c2 and its width to be 122.2±6.2±8.0 MeV/c2. We find no corresponding enhancement at 1750 MeV/c2 in K∗K, and again neglecting any possible interference effects we place limits on the ratio Γ(X(1750)→K∗K)/Γ(X(1750)→K+K−). Our results are consistent with previous photoproduction experiments, but, because of the much greater statistics, challenge the common interpretation of this enhancement as the φ(1680) seen in e+e− annihilation experiments.
