Updated cross section measurement of e+e- →k+K-J /ψ and KS0 KS0 J /ψ via initial state radiation at Belle

Abstract

The cross sections of the processes e+e-→K+K-J/ψ and KS0KS0J/ψ are measured via initial state radiation at center-of-mass energies between the threshold and 6.0 GeV using a data sample of 980fb-1 collected with the Belle detector on or near the Υ(nS) resonances, where n=1,2,...,5. The cross sections for e+e-→K+K-J/ψ are at a few pb level and the average cross section for e+e-→KS0KS0J/ψ is 1.8±0.6(stat)±0.3(syst)pb between 4.4 and 5.2 GeV. All of them are consistent with previously published results with improved precision. A search for resonant structures and associated intermediate states in the cross section of the process e+e-→K+K-J/ψ is performed. © 2014 American Physical Society.