Related papers: Bounds on QCD Instantons from HERA
High-precision HERA data corresponding to a luminosity of around 1 fb$^{-1}$ have been used in the framework of $eeqq$ contact interactions (CI) to set limits on possible high-energy contributions beyond the Standard Model to electron-quark…
Possible modes of asymptotic behavior of the amplitudes of hadron scattering in QCD are discussed. It is shown that the condition of triviality of the scattering matrix when the interaction of the fundamental fields is turned off leads to…
A QCD analysis of jet production in deep-inelastic scattering is presented. The studies are based on recent measurements of jet cross sections in the H1 experiment at HERA which are directly sensitive to the gluon density in the proton. The…
In high density QCD the hadron production stems from decay of mini-jets that have the transverse momenta of the order of the saturation scale. It is shown in this paper that this idea is able to describe in a unique fashion both the…
The measurement and QCD analysis of neutral and charged current cross sections at HERA are presented. For the kinematic range of four-momentum transfer Q^2 between approx. 1 GeV^2 and 30000 GeV^2 and Bjorken x between 0.0013 and 0.65 the…
QED Compton scattering at HERA is discussed in terms of the information it may reveal on the proton structure at low momentum transfers Q2. Detailed Monte Carlo studies are performed which show that the analysis of inelastic QED Compton…
The contribution of the nonperturbative quark-gluon interaction induced by the instantons to $g_1^p(x,Q^2)$ and $F_2^p(x,Q^2)$ structure functions is estimated. It is shown that nontrivial $Q^2$ dependence of the instanton contribution to…
We consider the instanton contributions for the production of a gluon jet with large transverse momentum in QCD. We find that Mueller's corrections corresponding to the rescattering of hard quanta are likely to remove contributions of large…
We compute the decay rate for the process $\eta_c\to p\bar p$ using an effective helicity-flipping proton-antiproton-gluon vertex which incorporates nonperturbative chiral symmetry breaking effects induced by instantons. We fix the strength…
A phenomenological study of the final combined HERA data on inclusive deep inelastic scattering (DIS) has been performed. The data are presented and investigated for a kinematic range extending from values of the four-momentum transfer,…
The cross section of diffractive deep-inelastic scattering ep \rightarrow eXp is measured, where the system X contains at least two jets and the leading final state proton is detected in the H1 Forward Proton Spectrometer. The measurement…
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…
General formula for inclusive gluon distribution on rapidities is obtained for the processes of multigluon production in classical instanton field with the first quantum correction. On the basis of this formula second correlation function…
Discovery of instantons in colliders will provide experimental evidence for the topological properties of the QCD vacuum. In this work, we propose jet correlation observables that can unambiguously discriminate between instanton-induced…
We discuss HERA data on the high energy behavior of the total gamma*p cross section and on diffraction in deep inelastic scattering. We outline their novelty in comparison with diffraction in high energy hadron hadron scattering. As a…
The cross section for the diffractive deep-inelastic scattering process $ep \to e X p$ is measured, with the leading final state proton detected in the H1 Forward Proton Spectrometer. The data analysed cover the range \xpom <0.1 in…
High energy scattering processes of charged particles are accompanied by radiation of hard photons. Emission collinear to the incident particles, which leads to a reduction of the effective beam energy, and the possibility to directly…
In QCD the spontaneous breaking of chiral symmetry and the U(1) axial anomaly can be understood considering instantons as the gauge configurations mediating quark-quark interaction. The existence of an exact zero mode solution of the Dirac…
A measurement is presented of elastic Deeply Virtual Compton Scattering e^+ + p -> e^+ + photon + p at HERA using data taken with the H1 detector. The cross section is measured as a function of the photon virtuality, Q^2, and the invariant…
Events with a (2+1) jet topology in deep-inelastic scattering at HERA are studied in the kinematic range 200 < Q^2< 10,000 GeV^2. The rate of (2+1) jet events has been determined with the modified JADE jet algorithm as a function of the jet…