Revealing transversity GPDs through the photoproduction of a photon and a ρ\rho meson

Photoproduction of a pair of particles with large invariant mass is a natural extension of collinear QCD factorization theorems which have been much studied for deeply virtual Compton scattering and deeply virtual meson production. We discuss the production of a photon and a meson, where the wide angle Compton scattering on a meson subprocess factorizes from generalized parton distribution. We calculate at dominant twist and leading order in $\alpha_s$, the production cross-section of a transversely polarized $\rho$ meson which is sensitive to chiral-odd GPDs, and show that it may be measurable in near future JLab experiments.Comment: 6 pages, 3 figures. Contribution to the proceedings of the 6th International Conference on Physics Opportunities at an Electron-Ion Collider (POETIC6), September 7-11, 2015, Palaiseau, France. The numerical plot (fig.3) has been corrected. arXiv admin note: text overlap with arXiv:1511.0437

Towards a complete next-to-logarithmic description of forward exclusive diffractive dijet electroproduction at HERA: real corrections

We studied the $ep\rightarrow ep+2jets$ diffractive cross section with ZEUS phase space. Neglecting the $t$-channel momentum in the Born and gluon dipole impact factors, we calculated the corresponding contributions to the cross section differential in $\beta=\frac{Q^{2}}{Q^{2}+M_{2jets}^{2}}$ and the angle $\phi$ between the leptonic and hadronic planes. The gluon dipole contribution was obtained in the exclusive $k_{t}$-algorithm with the exclusive cut $y_{cut}=0.15$ in the small $y_{cut}$ approximation. In the collinear approximation we canceled singularities between real and virtual contributions to the $q\bar{q}$ dipole configuration, keeping the exact $y_{cut}$ dependency. We used the Golec-Biernat - W\"usthoff (GBW) parametrization for the dipole matrix element and linearized the double dipole contributions. The results give roughly $\frac{1}{2}$ of the observed cross section for small $\beta$ and coincides with it for large $\beta.$Comment: 40 pages, 7 figure

Impact factor for high-energy two and three jets diffractive production

We present the calculation of the impact factor for the gamma(*) -> q qb g transition within Balitsky's high energy operator expansion. We also rederive the impact factor for the gamma(*) -> q qb transition within the same framework. These results provide the necessary building blocks for further phenomenological studies of inclusive diffractive deep inelastic scattering as well as for two and three jets diffractive production which go beyond approximations discussed in the litterature.Comment: 27 pages, 2 figure

Impact Factor for Exclusive Diffractive Dijet Production with NLO Accuracy

Relying on the shockwave approach, we present the main steps of the computation of the impact factor for the exclusive diffractive photo- or electro- production of a forward dijet with NLO accuracy. We provide details of the cancellation mechanisms for all the divergences which appear in the intermediate results.Comment: 4 pages, 1 figure; proceedings of "Diffraction 2016", International Workshop on Diffraction in High-Energy Physics, Acireale (Catania, Sicily), Sept. 2-8, 2016; to be published in the conference proceedings by AI

NLO exclusive diffractive processes with saturation

We present two NLO exclusive impact factors computed in the QCD shock wave approach. These are the very first steps towards precision studies of a wide range of high energy exclusive processes with saturation effects in $ep$, $eA$, $pp$ and $pA$ collisions.Comment: 8 pages, 2 figures, to appear in the proceedings of XXV International Workshop on Deep-Inelastic Scattering and Related Subject - DIS 2017, 3-7 April 2017, University of Birmingham, U

Paving the Way Towards Precision Physics in Saturation Studies Through Exclusive Diffractive Light Neutral Vector Meson Production

We perform the first next-to-leading order computation of the $\gamma^{(*)} \to V$ ($\rho, \phi, \omega$) impact factor in the QCD shockwave approach and in the most general kinematics. This paves the way to the very first quantitative study of high-energy nucleon and nucleus saturation beyond the leading order, in various processes to be measured in $ep$, $eA$, $pp$ and $pA$ collisions at existing and future colliders.Comment: 7 pages, 1 figur