Scaled momentum spectra of identified particles 
                        in the Breit frame at HERA

                          ZEUS Collaboration

                              Abstract

Scaled momentum distributions of identified particles, K0S and Lambda,
have been measured in deep inelastic ep scattering with the ZEUS
detector at HERA using an integrated luminosity of 290 pb^-1. The
evolution of these distributions with the photon virtuality, Q^2, was
studied in the kinematic region 10 < Q^2 < 40000 GeV^2. The
distributions were measured in the current fragmentation region of the Breit
frame. Next-to-leading-order QCD calculations including hadron-mass
effects were compared to the data. The calculations reproduce
reasonably well the trends of the measured distributions as functions
of Q^2 and the scaled momentum variable.