Abstract
We report the first double differential cross sections of two charged pions and kaons () in electron-positron annihilation as a function of the fractional energies of the two hadrons for any charge and hadron combination. The dependence of these dihadron cross sections on the topology (same, opposite hemisphere or anywhere) is also studied with the help of the event shape variable thrust and its axis. The ratios of these dihadron cross sections for different charges and hadron combinations directly shed light on the contributing fragmentation functions. For example, we find that the ratio of same-sign pion pairs over opposite-sign pion pairs drops toward higher fractional energies where disfavored fragmentation is expected to be suppressed. These dihadron results are obtained from a data sample collected near the resonance with the Belle detector at the KEKB asymmetric-energy collider. Extending the previously published single-pion and single-kaon cross sections, single-proton () cross sections are extracted from a data subsample.
16 More- Received 2 September 2015
DOI:https://doi.org/10.1103/PhysRevD.92.092007
© 2015 American Physical Society