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 root 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.