Related papers: Jet Physics and Event Shape Studies at HERA
The study of the inelastic scattering of hadrons has progressed in the last decade. With the availability of high-statistics data sets from HERA and the Tevatron, our understanding of high energy and high jet multiplicity events has become…
Next-to-leading order QCD predictions for 1-jet and 2-jet cross sections in polarized deep inelastic scattering at HERA energies are presented. Whereas the QCD corrections to the total polarized cross section are very large, only moderate…
The transverse momentum flow inside jets is a sensitive measure of internal jet structure. For the current jets in deep inelastic scattering this jet shape measure is determined at order alpha_s^2, i.e. with up to three partons inside a…
Studies of event shape observables at PETRA and LEP energies are presented. Previously published determinations of the strong coupling constant \alpha_s at \sqrt{s} = 35 and 44 GeV are complemented using new resummed QCD calculations for…
Jet cross sections were measured in charged current deep inelastic e+-p scattering at high boson virtualities Q^2 with the ZEUS detector at HERA II using an integrated luminosity of 0.36 fb^-1. Differential cross sections are presented for…
Recent results on diffraction at HERA are presented, focusing on the measurement of the inclusive diffractive cross section and on the study of two and three jets in diffractive ep scattering.
The latest results on jet cross sections in neutral current deep inelastic $ep$ scattering from the ZEUS Collaboration are presented. The new results were used to perform stringent tests of perturbative QCD and extract precise values of the…
The internal jet structure in dijet production in deep-inelastic scattering is measured with the H1 detector at HERA. Jets with transverse energies E(T,breit) > 5 GeV are selected in the Breit frame employing kt and cone jet algorithms in…
The QCD expectations concerning the deep inelastic lepton - hadron scattering at low $x$ and their phenomenological implications for HERA are summarised. Theoretical predictions for the structure function $F_2(x,Q^2)$ based on the leading…
Multijet production rates in neutral current deep inelastic scattering have been measured in the range of exchanged boson virtualities 10 < Q2 < 5000 GeV2. The data were taken at the ep collider HERA with centre-of-mass energy sqrt(s) = 318…
We present next-to-leading order calculations of one- and two-jet production in eP collisions at HERA for photon virtualities in the range 1<Q^2<100 GeV^2. Soft and collinear singularities are extracted using the phase space slicing method.…
Next-to-leading order corrections to jet cross sections in deep inelastic scattering at HERA are studied. The predicted jet rates allow for a precise determination of $\alpha_s(\mu_R)$ at HERA over a wide range of $\mu_R$. We argue, that…
A first determination of the strong coupling $\alpha_s(m_Z)$ in next-to-next-to-leading order (NNLO) from inclusive jet and dijet production cross sections in deep-inelastic scattering at HERA is presented. Data collected by the H1…
A new next-to-leading order Monte Carlo program for the calculation of jet cross sections in photoproduction is described. The contributions from both resolved and direct components are included to O(\alpha \alpha_s^2). Properties of the…
NLO corrections to jet cross sections in DIS at HERA are studied, with particular emphasis on the two jet final state. High jet transverse momenta are a good criterion for the applicability of fixed order perturbation theory. A ``natural''…
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 < 15000 GeV^2 and transverse jet energies 7 < E_T < 60 GeV. The analysis is based on data…
Complete next-to leading order QCD predictions for (2+1) jet cross sections and jet rates in deep inelastic scattering (DIS) based on a new parton level Monte Carlo program are presented. All relevant helicity contributions to the total…
Studies on the structure of the photon are presented by means of the extraction of a leading order effective parton distribution in the photon and measurements of inclusive jet differential cross sections in photoproduction. Measurements of…
The analysis of event shape variables enable studies of QCD and determinations of alpha-s, but require predictions to next-to-leading order. The predictions of two next-to-leading order programs are compared for current jet thrust, current…
Three-jet production is studied for the first time in deep-inelastic positron-proton scattering. The measurement carried out with the H1 detector at HERA covers a large range of four-momentum transfer squared 5 < Q^2 < 5000 GeV^2 and…