[Show abstract][Hide abstract] ABSTRACT: Inclusive baryon-antibaryon pair production was studied in two-photon events which were collected at thee
− collider TRISTAN, and correspond to an integrated luminosity of 303 pb−1. Correlations between a baryon and an antibaryon were studied for their flavors (p orΛ) and their momentum vectors. The experimental results were compared with the expectations from a jet-fragmentation Monte
Carlo simulation. We have found that although the ratios of the cross sections of different baryon-flavor combinations are
consistent with the Monte Carlo expectations, the cross section shows an excess over the Monte Carlo expectation in a low
invariant-mass region of final-state particles at large angles, that indicates a significant contribution from higher-order
QCD or non-perturbative effects. The experimental data show no narrow azimuthal-angle correlation, which is expected from
a jet-fragmentation Monte Carlo. A search for exclusiveΛ pair production has also been made. We have no candidates and have obtained the upper limit for the cross section.
No preview · Article · Nov 1995 · Zeitschrift für Physik C
[Show abstract][Hide abstract] ABSTRACT: The differential cross sections for e+e-→e +e- and e+e-→γγ have been measured at the highest energy of √s=52 GeV in e +e- collisions. The process e+e -→e+e- is well understood within the framework of the standard model of electroweak interactions. The reaction e +e- →γγ is found to be in good agreement with QED. The 95% confidence limits obtained for the QED cut-off parameters are A+>61 GeV and A->72 GeV for e+e -→γγ.
No preview · Article · Nov 1987 · Journal of the Physical Society of Japan