Related papers: QCD-Instantons at HERA
We consider the instanton-induced cross section for production of a gluon jet with large transverse momentum in QCD and point out that Mueller's corrections corresponding to the rescattering of hard quanta are likely to remove contributions…
Brief review of the diffractive physics at HERA, stressing QCD aspects.
The instanton--antiinstanton pair induced asymptotics of perturbation theory expansion for QCD correlators is considered. It is argued that though the true asymptotics is dominated by renormalon, the instanton-induced contribution may…
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 present integrated subtraction terms and finite remainders for arbitrary processes with massless partons at hadron and lepton colliders in the context of the nested soft-collinear subtraction scheme. These results provide the very last…
An increased precision of HERA data allows studies of exclusive processes in their transition from soft to hard interactions as well as in the pQCD domain. The recent measurements of vector meson production and Deeply Virtual Compton…
We demonstrate that perturbative QCD allows one to calculate the absolute cross section of diffractive exclusive production of photons at large $Q^2$ at HERA, while the aligned jet model allows one to estimate the cross section for…
We perform a study of the non-perturbative dynamics of the light-quark sector of QCD, based on some recent results of lattice simulations with chiral fermions. We analyze some correlators that are designed to probe the Dirac structure of…
Recent results from the HERA experiment H1 on the longitudinal stucture function $F_{L}$ of the proton are presented. They include proton structure function analyses with particular emphasis on those kinematic regions which are sensitive to…
Recent theoretical developments to calculate cross sections of hadronic objects in the high energy limit are summarised and experimental attempts to establish the need for new QCD effects connected with a resummation of small hadron…
We show how to do semiclassical nonperturbative computations within the worldline approach to quantum field theory using ``worldline instantons''. These worldline instantons are classical solutions to the Euclidean worldline loop equations…
I address the question of how much of QCD in the chiral limit is reproduced by instantons. After reconstructing the instanton content of smoothed Monte Carlo lattice configurations, I compare hadron spectroscopy on this instanton ensemble…
I discuss the possible instanton-induced multiparticle production in hard processes in QCD Figures are available upon request
We study the magnetic hysteresis in the random field Ising model in 3D. We discuss the disorder dependence of the coercive field H_c, and obtain an analytical description of the smooth part of the hysteresis below and above H_c, by…
Infrared safe differential cross sections, such as event shape distributions, can be measured over wide kinematic ranges, from regions where fixed order calculations are adequate to regions where nonperturbative dynamics dominate. Such…
We analyse recent data on the production of forward neutrons in deep inelastic scattering at HERA in the framework of a perturbative QCD description for semi-inclusive processes, which includes fracture functions. Using a model estimate for…
We perform a numerical study of the QCD corrections to the structure function $F_L(x,Q^2)$ in the HERA energy range. The $K$--factors are of $O(30%)$ and larger in parts of the kinematic range. The relative corrections to…
We show that the instanton-induced inelastic processes, leading to multi-gluon production in in high-energy parton-parton scattering, are considerably enhanced over the quasi-elastic ones, by a factor of 100. The basic instanton-induced…
We compute instantonic effects in globally consistent T^6/Z2xZ2 orientifold models with discrete torsion and magnetised D-branes. We consider fractional branes and instantons wrapping the same rigid cycles. We clarify and analyse in detail…
Data from the HERA collider experiments, H1 and ZEUS, have been fundamental to the rapid recent development of our understanding of the partonic composition of the proton and of QCD. This report focuses on inclusive measurements of neutral…