Measurement of Multijet Production in DIS and Determination of the Strong Coupling Constant

TL;DR

This paper measures multijet production in deep-inelastic scattering at HERA, compares results with QCD predictions, and determines the strong coupling constant with high precision.

Contribution

It provides the first comprehensive measurement of multijet cross sections across a wide Q^2 range and extracts the strong coupling constant from these data.

Findings

Multijet cross sections agree with NLO QCD calculations.

The strong coupling constant is determined with competitive precision.

Results improve understanding of QCD in high-energy scattering.

Abstract

Inclusive jet, dijet and trijet differential cross sections have been measured in neutral current deep-inelastic scattering for exchanged boson virtualities $150 < Q^2 < 15000$ GeV$^2$ with the H1 detector at HERA using an integrated luminosity of 351 pb$^{-1}}$. The multijet cross sections are presented as a function of $Q^2$, the transverse momentum of the jet $P_T$ (the mean transverse momentum for dijets and trijets) and the proton's longitudinal momentum fraction of the parton participating in the hard interaction $\xi$. The cross sections are compared to perturbative QCD calculations at next-to-leading order and the value of the strong coupling $\alpha_s(M_Z)$ is determined.