Angular analysis of the e + e - → D (*)± D *∓ process near the open charm threshold using initial-state radiation

Abstract

We report a new measurement of the exclusive e+e-→D(∗)±D∗ cross sections as a function of the center-of-mass energy from the D(∗)±D∗ threshold through s=6.0 GeV, using the initial-state radiation technique. The analysis is based on a data sample collected with the Belle detector with an integrated luminosity of 951 fb-1. The accuracy of the cross section measurement is increased by a factor of 2 over the first Belle study. We perform the first angular analysis of the e+e-→D∗±D∗ process and decompose this exclusive cross section into three components corresponding to the D∗ helicities.