Measurements of electroweak Wjj production and constraints on anomalous gauge couplings with the ATLAS detector

Measurements of the electroweak production of a W boson in association with two jets at high dijet invariant mass are performed using root s = 7 and 8 TeV proton-proton collision data produced by the Large Hadron Collider, corresponding respectively to 4.7 and 20.2 fb(-1) of integrated luminosity collected by the ATLAS detector. The measurements are sensitive to the production of a W boson via a triple-gauge-boson vertex and include both the fiducial and differential cross sections of the electroweak process

Measurement of the inclusive cross-section for the production of jets in association with a Z boson in proton-proton collisions at 8 TeV using the ATLAS detector

The inclusive cross-section for jet production in association with a Z boson decaying into an electron–positron pair is measured as a function of the transverse momentum and the absolute rapidity of jets using 19.9 fb −1 of s√=8 TeV proton–proton collision data collected with the ATLAS detector at the Large Hadron Collider. The measured Z + jets cross-section is unfolded to the particle level. The cross-section is compared with state-of-the-art Standard Model calculations, including the next-to-leading-order and next-to-next-to-leading-order perturbative QCD calculations, corrected for non-perturbative and QED radiation effects. The results of the measurements cover final-state jets with transverse momenta up to 1 TeV, and show good agreement with fixed-order calculations

Observation of hard processes in rapidity gap events in gamma p interactions at HERA

Events with no hadronic energy flow in a large interval of pseudo-rapidity in the proton direction are observed in photon-proton interactions at an average centre of mass energy 〈$\sqrt {s_{ \gamma p}}$〉 of 200 GeV These events are interpreted as photon diffractive dissociation. Evidence for hard scattering in photon diffractive dissociation is demonstrated using inclusive single particle spectra, thrust as a function of transverse energy, and the observation of jet production. The data can be described by a Monte Carlo calculation including hard photon-pomeron scattering

Determination of the strong coupling constant from jet rates in deep inelastic scattering

Jet rates in deep inelastic electron proton scattering are studied with the H1 detector at HERA for momentum transfers squared between 10 and 4000 GeV$^2$ . It is shown that they can be quantitatively described by perturbative QCD in next to leading order making use of the parton densities of the proton and with the strong coupling constant $\alpha_s$ as a free parameter. The measured value, $\alpha_s ( M_Z^2 ) = 0.123 ± 0.018$, is in agreement both with determinations from $e^+ e^−$ annihilation at LEP using the same observable and with the world average