26-30 March 2012
University of Bonn
Europe/Berlin timezone

Scaled Momentum Distributions for K^0_s and Lambda/anti-Lambda in DIS at HER

28 Mar 2012, 14:50
Small Lecture Hall, Mathematical Institute (University of Bonn)

Small Lecture Hall, Mathematical Institute

University of Bonn

Hadronic final states Hadronic final states


Iris Abt (Werner-Heisenberg-Institut)


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)

Presentation Materials