Leptonic and Charged Kaon Decay Modes of the ϕ Meson Measured in Heavy-Ion Collisions at the CERN Super Proton Synchrotron

Le résumé fourni par la source

We report on results of a measurement of $\ensuremath{\phi}$ meson production in central Pb-Au collisions at ${E}_{\mathrm{lab}}=158A\text{ }\text{ }\mathrm{GeV}$. For the first time in the history of high energy heavy-ion collisions, $\ensuremath{\phi}$ mesons were reconstructed both in the ${K}^{+}{K}^{\ensuremath{-}}$ and the dilepton decay channels in the same experiment. This measurement yields rapidity densities near midrapidity, from the two decay channels, of $2.05\ifmmode\pm\else\textpm\fi{}0.14(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.25(\mathrm{syst})$ and $2.04\ifmmode\pm\else\textpm\fi{}0.49(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.32(\mathrm{syst})$, respectively. The shape of the measured transverse momentum spectrum is also in close agreement in both decay channels. The data rule out a possible enhancement of the $\ensuremath{\phi}$ yield in the leptonic over the hadronic decay channel of a factor 1.6 or larger at the 95% C.L. This rules out the discrepancy reported in the literature between measurements of the hadronic and dimuon decay channels by two different experiments.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.