Abstract submitted to the
         International Europhysics Conference on High Energy Physics
                  July 12 - 18, 2001, Budapest, Hungary
_________________________________________________________________________




         Inclusive jet cross sections in neutral current deep inelastic
       scattering in the Breit frame and determination of alpha_s at HERA

                    
                               ZEUS Collaboration



                                    Abstract


    Inclusive jet differential cross sections for the reaction e^+p ->
    e^+ + jet(s) + X have been measured in neutral current interactions 
    at Q^2 > 125 GeV^2 with the ZEUS detector at HERA using an integrated 
    luminosity of 38 pb^{-1}. Jets are identified in the Breit frame 
    using the longitudinally invariant k_T-cluster algorithm. 
    Measurements of differential inclusive jet cross sections are
    presented as functions of the jet transverse energy, E_Tjet^b, jet 
    pseudorapidity, eta_jet^b, jet azimuthal angle, phi_jet^b, and Q^2 for
    jets with E_Tjet^b > 8 GeV. Next-to-leading-order QCD calculations 
    give a good description of the measurements at high Q^2 or high 
    E_Tjet^b. The measured azimuthal distribution is non-uniform. Its 
    shape is well described by the QCD prediction. A QCD analysis of the
    measured inclusive jet cross sections at high Q^2 or high E_Tjet^b
    allows a precise determination of alpha_s(M_Z) and a detailed
    estimate of the uncertainties of the NLO QCD predictions arising from 
    the parton distribution functions of the proton. The value of 
    alpha_s(M_Z), as determined from the QCD fit to dsigma/dQ^2 for 
    Q^2 > 500 GeV^2, is
    alpha_s(M_Z) = 0.1190 \pm 0.0017 (stat.)
                          ^{+ 0.0049}_{- 0.0023} (syst.)
                          ^{+ 0.0026}_{-0.0026} (th.).