Measurement and QCD analysis of jet cross sections in deep-inelastic positron-proton collisions at $\sqrt{s}$ of 300 GeV

Abstract.

Jet production is studied in the Breit frame in deep-inelastic positron-proton scattering over a large range of four-momentum transfers $5 < Q^2 < 15 000 {\rm GeV}^2$ and transverse jet energies $7 < E_T < 60$GeV. The analysis is based on data corresponding to an integrated luminosity of ${\cal L}_{\rm int} \simeq 33 {\rm pb}^{-1}$ taken in the years 1995–1997 with the H1 detector at HERA at a center-of-mass energy $\sqrt{s} =300$GeV. Dijet and inclusive jet cross sections are measured multi-differentially using $k_\perp$ and angular ordered jet algorithms. The results are compared to the predictions of perturbative QCD calculations in next-to-leading order in the strong coupling constant $\alpha_s$. QCD fits are performed in which $\alpha_s$ and the gluon density in the proton are determined separately. The gluon density is found to be in good agreement with results obtained in other analyses using data from different processes. The strong coupling constant is determined to be $\alpha_s(M_Z)=0.1186 \pm 0.0059$. In addition an analysis of the data in which both $\alpha_s$ and the gluon density are determined simultaneously is presented.