Speaker
Iris Abt
(Werner-Heisenberg-Institut)
Description
Scaled momentum distributions for the strange hadrons K0s and
Lambda/Lambdabar were measured in deep inelastic ep scattering
with the ZEUS detector at HERA using an integrated luminosity of 330 pb-1. The evolution of these distributions with the photon virtuality,
Q2, was studied in the kinematic region 10 < Q2 < 40000 GeV2 and
0.001 < x < 0.75, where x is the Bjorken scaling variable. Clear
scaling violations are observed. Predictions based on different
approaches to fragmentation were compared to the measurements. Tuned leading-logarithm parton-shower Monte Carlo calculations
interfaced to the Lund string fragmentation model describe the data reasonably well in the whole range measured. Next-to-leading-order QCD calculations based on fragmentation functions, FFs, extracted from e+e- data alone, fail to describe the measurements. The calculations based on FFs extracted from a global analysis including e+e-, ep and pp data give an improved description. The measurements presented in this paper have the potential to further constrain the FFs of quarks, anti-quarks and gluons yielding K0s and Lambda/Lambdabar strange hadrons.
Primary author
Iris Abt
(Werner-Heisenberg-Institut)
