Collins asymmetries in inclusive charged $KK$ and $K\ddot{I}€$ pairs produced in $e^{+}{e}^{-}$ annihilation

Abstract

We present measurements of Collins asymmetries in the inclusive process $e^{+}{e}^{-}\to h_1{h}_{2}X$, $h_1{h}_2=KK,K\ddot{I}€,\ddot{I}€\ddot{I}€$, at the center-of-mass energy of 10.6 GeV, using a data sample of 468 fb${}^{-1}$ collected by the BaBar experiment at the PEP-II $B$ factory at SLAC National Accelerator Center. Considering hadrons in opposite thrust hemispheres of hadronic events, we observe clear azimuthal asymmetries in the ratio of unlike- to like-sign, and unlike- to all charged $h_1{h}_2$ pairs, which increase with hadron energies. The $K\ddot{I}€$ asymmetries are similar to those measured for the $\ddot{I}€\ddot{I}€$ pairs, whereas those measured for high-energy $KK$ pairs are, in general, larger.

7 pages, 4 postscript figures, 5 pages of Supplemental Material