Physics with jets in association with a $Z$ boson in pp-collisions with the ATLAS detector at the Large Hadron Collider

This thesis presents the measurements of the production cross section of jets in association with a $Z$ boson in pp-collisions at $\sqrt{s}$ = 7 TeV with an integrated luminosity of $\int L \text{d}t$ = 36 pb${−1}$ and $\int L \text{d}t$ = 4.6 fb$^{−1}$ recorded by the ATLAS experiment at the Large Hadron Collider in Geneva. Inclusive and differential $Z(\to e^+e^−)$ + jets cross sections are measured for jets with a transverse momentum $p_{T}^{jet} > 30$ GeV and rapidity $\left | y^{jet} \right |$ < 4.4. The datasets allow to exploit the data in kinematic regimes which were not accessible before and can be used to probe the $Z/\gamma ^*$ + jets modelling in typical phase-space regions expected for the Higgs boson decay and searches for new physics. The results are unfolded to particle level and compared to predictions from different Monte Carlo generators and next-to-leading-order perturbative QCD calculations.