Related papers: Diffractive Dijet Production and Nuclear Shadowing…
Recent data on diffractive photoproduction of dijets are analyzed within the framework of fracture functions and paying special attention to the consequences of the use of different rapidity gap definitions in order to identify diffractive…
We explore how nuclear modifications to the nucleon parton distributions affect production of high transverse momentum hadrons in deuteron-nucleus collisions. We calculate the charged hadron spectra to leading order using standard…
We have calculated the diffractive dijet cross section in low-Q^2 ep scattering in the HERA regime. The results of the calculation in LO and NLO are compared to recent experimental data of the H1 collaboration. We find that in LO the…
In diffractive interactions of protons or nuclei a violent collision can occur that leaves the forward going particle completely intact -with probability determined by the structure of the proton or nucleus. At very high energies these…
Measurements are presented of single and double-differential dijet cross sections in diffractive photoproduction based on a data sample with an integrated luminosity of 47 pb^-1. The events are of the type ep -> eXY, where the hadronic…
Multiple parton interactions in relativistic heavy ion reactions result in transverse momentum diffusion and medium induced non-Abelian energy loss of the hard probes traversing cold and hot nuclear matter. A systematic study of the…
Medium effects on the production of high-$p_{\rm T}$ particles in nucleus-nucleus (AA) collisions are generally quantified by the nuclear modification factor ($R_{\rm AA}$), defined to be unity in absence of nuclear effects. Modeling…
In the target rest frame and at high energies, Drell-Yan (DY) dilepton production looks like bremsstrahlung of massive photons, rather than parton annihilation. The projectile quark is decomposed into a series of Fock states. Configurations…
Di-hadron and di-jet correlation measurements in proton-nucleus ($p$+A) and electron--nucleus collisions are widely motivated as sensitive probes of novel, non-linear QCD saturation dynamics in hadrons, which are particularly accessible in…
Results on soft and hard diffraction in $pp$ and $\bar pp$ collisions are reviewed with emphasis on factorization and scaling properties of differential cross sections. While conventional factorization breaks down at high energies, a…
The phenomenon of shadowing of nuclear structure functions at small values of Bjorken-$x$ is analyzed. First, multiple scattering is discussed as the underlying physical mechanism. In this context three different but related approaches are…
We calculate, in the Glauber-Mueller approach, the ratio of the diffractive dissociation cross section to the total cross section on nuclei. We observe that shadowing corrections (SC) are significant, in the calculated $\ddt$ ratio but they…
We study inclusive heavy quark and exclusive heavy quark pair production in pp, pA and AA interactions. Intrinsic transverse momentum is introduced in pp interactions. Nuclear effects, limited to $k_T$ broadening and nuclear shadowing, are…
We calculate pseudorapidity ($\eta$) asymmetry in $pA$ and $dA$ collisions in a pQCD-improved parton model. With the calculations tuned to describe existing spectra from $pp$ collisions and asymmetric systems at midrapidity and large…
We study various conceivable photoproduction reactions in a polarized ep collider mode of HERA with respect to their sensitivity to the proton's polarized gluon distribution. A special emphasis is put on the `resolved' part of the cross…
Efforts to observe color transparency in the reactions: (e,e'p), (p,pp) and coherent nuclear diffractive dissociation of pions into two jets are reviewed.
The interaction of spatially small dipoles with nucleons, nuclei is calculated in the DGLAP approximation at the top of HERA energies and found to be close to the $S$-channel unitarity limit in the case of the color octet dipoles. The DGLAP…
Photoproduction of heavy quarks and exclusive production of vector mesons in ultraperipheral proton-nucleus and nucleus-nucleus collisions depend significantly on nuclear gluon distributions. In the present study we investigate…
Diffraction plays an exceptional role in DIS off heavy nuclei. First, diffraction into hard dijets is an unique probe of the unintegrated glue in the target. Second, because diffraction makes 50 per cent of total DIS off a heavy target,…
Two aspects of high-energy \pp collisions share common phenomenological elements: (a) A correlation between jet production and \pp centrality is suggested by the transverse partonic structure of hadrons inferred from deep-inelastic…