Related papers: Odderon induced Pion-Photoproduction at e+e- Colli…
We present a study of the central exclusive production of the $K^{+} K^{-}$ pairs in proton-proton collisions at high energies. We consider diffractive mechanisms including the $K^{+} K^{-}$ continuum, the dominant scalar $f_{0}(980)$,…
We report on the investigation of dielectron production in tagged quasi-free neutron-proton collisions by using a deuteron beam of kinetic energy 1.25 GeV/u inpinging on a liquid hydrogen target. Our measurements with HADES confirm a…
There is a significant discrepancy between the values of the proton electric form factor, $G_E^p$, extracted using unpolarized and polarized electron scattering. Calculations predict that small two-photon exchange (TPE) contributions can…
We discuss the $p p \to p p \gamma$ reaction at the LHC. We consider diffractive classical bremsstrahlung mechanisms including effects of non point-like nature of protons. In addition, we take into account (vector meson)-pomeron,…
We extract the two-photon exchange (TPE) contributions to electron--proton elastic scattering using two parametrizations and compare the results to different phenomenological extractions and direct calculations of the TPE effects. We find…
There seem to be recently an evidence for $C = -1$ odderon exchange in proton-proton elastic scattering at high energies. Here we discuss three different central-exclusive-production processes $pp \to pp (\phi \to K^{+}K^{-})$, $pp \to pp…
Measurements of soft and hard diffractive processes have been performed at the Tevatron p-pbar collider during the past decade. Diffractive events are studied by means of identification of one or more rapidity gaps and/or a leading…
This paper serves as a report on the large amount of analysis done in conjunction with the polarized proton program at RHIC. This comprises elastic scattering data of protons on protons in colliding beam or fixed target mode and proton…
We evaluate the large momentum transfer $J/\psi$ photoproduction with rapidity gaps in ultraperipheral proton-ion collisions at the LHC which provides an effective method of probing dynamics of large t elastic hard QCD Pomeron interactions.…
The possibility to use the exclusive $pp \to pp \phi$ and $pp \to pp \phi \phi$ reactions in identifying the odderon exchange is discussed. So far there is no unambiguous experimental evidence for the odderon, the charge conjugation $C =…
We study the contribution of double parton scattering (DPS) to the associated production of $J/\psi$ mesons and photons with large transverse momenta in proton-proton collisions. Cross sections are computed within high-energy factorization…
We consider hard diffractive events in proton-proton collisions at the LHC, in which both protons escape the collision intact. In such double Pomeron exchange processes, we propose to measure dijets and photon-jet final states, and we show…
The rates of inclusive photo- and electroproduction of the eta_c meson: gamma* + p -> eta_c + X are calculated in the triple Regge region, integrated over the diffractive mass X. For the Regge exchanges we use the hard Pomeron and Odderon,…
The elastic production of top quark pairs in $pp$ collisions at low and high luminosity regimes is investigated in detail. We extend the study performed in Phys. Rev. D102, 074014 (2020) which has demonstrated that the sum of two…
We consider proton diffraction dissociation in the dipole Pomeron model, where the Pomeron is represented by a double pole in the $J-$plane, and show that unitarity can be satisfied without decoupling of the triple Pomeron vertex.…
Recent results on the slope of the $pp$ diffraction cone measured by TOTEM at $7$ and $8$ GeV show an unexpected rapid rise in $s$, close to $B(s)\sim \ln^2$, rather than $\ln s$, typical of the Regge-pole predictions. We show that the new…
We discuss first the discovery of the odderon by the TOTEM and D0 collaborations. We then describe the gap between jets measurements sensitive to the high gluon density regime and the possible observation of saturation phenomenon in Pb Pb…
The LHC has released precise measurements of elastic proton-proton scattering that provide a unique constraint on the asymptotic behavior of the scattering amplitude at high energies. Recent reanalyses of part of these data indicate that…
The UA8 experiment previously reported the observation of jets in diffractive events containing leading protons (``hard diffraction''), which was interpreted as evidence for the partonic structure of an exchanged Reggeon, believed to be the…
High-energy hadronic reactions with proton-to-neutron transitions (and vice versa) with small momentum transfer allow to study the properties of nearly on-shell pions, which cannot be accessed otherwise. We overview the recent results for…