Angular Analysis of the e⁺e⁻ → D^(*)±D^*∓ Process Near the Open Charm Threshold with Initial-State Radiation

Abstract

The results of measurements of the exclusive cross section for the e⁺e⁻ → D^(*)±D^*∓ process near the open charm threshold with initial-state radiation are presented. The analysis is based on the experimental data collected with the Belle detector at energies $\sqrt s$ equal to ϒ(4S), ϒ(5S) production energies, and energies of the nearby continuum corresponding to an integrated luminosity of 951 fb⁻¹. The accuracy of the measurements of the cross sections is twice higher in comparison with the previous results of the Belle collaboration. An angular analysis is performed for the final state D*⁺D*⁻ for the first time with the result that the cross section is decomposed into three components corresponding to the possible combinations of D*-meson polarizations in the final state.