Inclusive pi0 and K0s Production in Two-Photon Collisions at LEP

TL;DR

This paper measures inclusive pi0 and K0s production in two-photon collisions at LEP, revealing soft and perturbative QCD processes through differential cross sections across a range of transverse momenta.

Contribution

It provides the first detailed measurement of pi0 and K0s production in two-photon collisions at LEP energies, comparing results with QCD predictions.

Findings

Soft processes dominate at low pt with exponential behavior.

Perturbative QCD processes become significant at higher pt with power-law behavior.

Data agree with Monte Carlo and NLO QCD calculations.

Abstract

The reactions ee->ee+pi0+X and ee->ee+K0s+X are studied using data collected at LEP with the L3 detector at centre-of-mass energies between 189 and 202 GeV. Inclusive differential cross sections are measured as a function of the particle transverse momentum pt and the pseudo-rapidity. For pt < 1.5 GeV, the pi0 and K0s differential cross sections are described by an exponential, typical of soft hadronic processes. For pt > 1.5 GeV, the cross sections show the presence of perturbative QCD processes, described by a power-law. The data are compared to Monte Carlo predictions and to NLO QCD calculations.