Related papers: QCD and total cross-sections: photons and hadrons
We present a QCD calculation of the transverse momentum distribution of photon pairs produced at hadron colliders, including all-orders soft-gluon resummation valid at next-to-next-to-leading logarithmic accuracy. We specify the region of…
In certain situations, such as one-particle inclusive processes, it is possible to model the hadronization through Fragmentation Functions (FFs), which are universal non-perturbative functions extracted from experimental data through…
We consider the photoproduction of two hadrons in polarized lepton-nucleon collisions in the framework of perturbative QCD at the next-to-leading order accuracy. After illustrating how to obtain the experimentally relevant observables, a…
We investigate the QED Compton process (QEDCS) in $e p \to e \gamma p$ and $e p \to e \gamma X$, together with the major background coming from the virtual Compton scattering (VCS), where the photon is emitted from the hadronic vertex. We…
We report on the current status of knowledge on inclusive quarkonium production in high-energy photon-photon collisions. As a perspective for the LHC, we compute various production cross sections via direct photon-photon fusion in…
A new Monte Carlo program for photohadronic interactions of relativistic nucleons with an ambient photon radiation field is presented. The event generator is designed to fulfil typical astrophysical requirements, but can also be used for…
We discuss diffractive photon-production of vector mesons in holographic QCD. At large $\sqrt{s}$, the QCD scattering amplitudes are reduced to the scattering of pair of dipoles exchanging a closed string or a pomeron. We use the…
In this note we address the issue of theoretical estimates of the hadronic cross-sections for \gamgam processes. We compare the predictions of the minijet model with data as well as other models, highlighting the band of uncertainties in…
We make a QCD-inspired parameterization of all accelerator data on forward proton-proton and antiproton-proton scattering amplitudes. Using vector dominance and the additive quark model, we show that the same parameters also fit gamma p and…
Making use of the hybrid Regge-plus-resonance model, we investigate the process of kaon photoproduction off the proton target. We present a new model whose free parameters were adjusted to data in and above the resonance region and which…
The process of exclusive vector meson production (gamma gamma to J/psi rho^0) is studied for almost real photons. This process may be reduced to photoproduction of J/psi off the rho^0 meson. We discuss the possibility of extracting the…
We study the exclusive photoproduction of a photon-meson pair with a large invariant mass, working in the QCD factorisation framework. Explicitly, we consider a $ \rho $-meson or a charged $ \pi $ in the final state. This process gives…
Using vector meson dominance we calculate the $\gamma\gamma$ total cross section from data on $pp$, $p\bar p$ and $\gamma p$ total cross sections. Our result agrees with recent high energy measurements performed by the L3 experiment at the…
A short review of leading term QCD predictions vs those of the handbag model for large angle cross sections \gamma\gamma --> P_2 P_1 (P is the pseudoscalar meson \pi^{\pm,o}, K^{\pm,o}, \eta), and for \gamma\gamma --> V_2 V_1 (V is the…
An earlier developed model for vector meson photoproduction, based on a dipole Pomeron exchange, is extended to electroproduction. Universality of the non linear Pomeron trajectory is tested by fitting the model to ZEUS and H1 data as well…
We present a complete set of transverse momentum dependent and collinear parton densities including the photon over a wide phase space. The photon density appears when evolving parton distributions with QED corrections. The photons are…
We consider the exclusive photo-production of a photon-meson pair with a large invariant mass, working in the QCD factorisation framework. Explicitly, we consider a $ \rho $-meson or a charged $ \pi $ in the final state. This process gives…
The cross sections of heavy quark production in $pp$ collision and for their photo- and electroproduction are calculated in the framework of QCD. The virtual nature of the interacting gluons as well as their transverse motion and different…
In this talk estimates are presented of the odderon contributions to the exclusive J/psi and Upsilon production cross-sections at the Tevatron and the Large Hadron Collider. The obtained cross-sections are compared to cross-sections of the…
We present a first estimate of the cross-section for the exclusive process gamma^*_L (Q_1^2) gamma^*_L(Q_2^2) -> rho^0_L rho^0_L, which will be studied in the future high energy e^+ e^- linear collider. As a first step, we calculate the…