Determination of $\alpha_{s}$ in NNLO QCD using H1 jet cross section measurements

Measurements of jet cross sections in neutral current deep-inelastic scatter-ing (NC DIS) using data taken with the H1 detector at HERA are accomplishedby theprecision measurement of double-differential inclusive jet, dijet and trijet cross sectionsat low photon virtualities 5.5 < Q2 < 80 GeV2, and by extending previous inclusivejet measurements in the range 150 < Q2 < 15000 GeV2 to low transverse jet momenta 5 < PT < 7 GeV. The strong coupling constant at the Z-boson mass, αs(mZ), is deter-mined in next-to-next-to-leading order (NNLO) QCD using H1 inclusive jetand dijetcross section measurements. Complementary, αs(mZ) is determined together with parton distribution functions of the proton (PDFs) from jet and inclusive DIS data measuredby the H1 experiment. The running of the strong coupling is tested at different valuesof the renormalisation scale and the results are found to be in agreement with the QCD expectations