Abstract submitted to the
         XXXth International Conference on High Energy Physics
                July 27 - August 2, 2000, Osaka, Japan
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              Measurement of differential cross sections for dijet
              production in neutral current DIS at high Q^2 and
                       determination of alpha_s


                    
                               ZEUS Collaboration





                                    Abstract


    Dijet production has been studied in neutral current DIS for 470 <
Q^2 < 20000 GeV^2 with the ZEUS detector at HERA, using an integrated
luminosity of 38 pb^-1.  Jets are found in the Breit frame using the
longitudinally invariant k_T-cluster algorithm. Dijet differential
cross sections and rates have been measured in a kinematic region
where theoretical and experimental uncertainties are small.  The data
are well described by NLO QCD. A QCD fit of the dijet rate and cross
section as a function of Q^2 allows both a precise determination of
the strong coupling constant and a test of its energy-scale
dependence.