Related papers: Paving the Way Towards Precision Physics in Satura…
Inclusive eta production at hadron colliders is considered,based on evaluation of eta fragmentation functions at next to leading order. Absolute predictions at LHC and SSC are presented, including the ratio $\eta/\pi^0$, together with the…
We summarize the current theoretical and experimental status of the spectral changes of vector mesons ($\rho$, $\omega$, $\phi$) at finite baryon density. Various approaches including QCD sum rules, effective theory of hadrons and bag…
In this work, we present a next-to-leading-order (NLO) study of $J/\psi + \gamma$ production via photon-photon fusion in proton-proton ultraperipheral collisions (UPCs) at $\sqrt{s_{NN}} = 14$ TeV. The calculation is performed within the…
A detailed study of fragmentation of vector mesons at the next-to-leading order (NLO) is given for e^+ e^- scattering. A model with broken SU(3) symmetry uses three input fragmentation functions \alpha(x, Q^2), \beta(x,Q^2) and…
We address the long-standing problem of negative decay and production rates in perturbative QCD for exclusive processes by proposing amplitude-level NRQCD factorization as a systematic prescription. Building on this, we present the first…
We illustrate the progress of covariant QCD phenomenology for the description of meson coupling constants and form factors. As examples, we discuss the $\rho\pi\pi$ and $\gamma \pi\rho$ interactions, the $\rho$ contribution to the pion…
We evaluate in the next-to-leading approximation the forward impact factor for the virtual photon to light vector meson transition in the case of longitudinal polarization. We find that in the hard kinematic domain, both in the leading and…
In this talk, we present the CGC/saturation approach of Ref.[C.~Contreras, E.~Levin, R.~Meneses and M.~Sanhueza,Eur. Phys. J. C 80 (2020) no.11, 1029] and its parameters determined from the combined HERA data. This model features an…
Unlike the bewildering situation in the $\gamma\gamma^*\to \pi$ form factor, a widespread view is that perturbative QCD can decently account for the recent \textsc{BaBar} measurement of $\gamma\gamma^*\to \eta_c$ transition form factor. The…
A next-to-leading order correction to the high-energy factorization limit of radiation spectrum from an ultrarelativistic electron scattering in an external field is evaluated. Generally, it does not express through scattering…
We introduce a new technique to calculate perturbative corrections to neutron-deuteron ($nd$) scattering that does not require calculation of the full off-shell scattering amplitude. Its relation to the more familiar partial-resummation…
We review recent progress in next-to-next-to-leading order (NNLO) perturbative QCD calculations with special emphasis on results ready for phenomenological applications. Important examples are new results on structure functions and jet or…
Recent developments in theory on the calculation of \gamma^* \gamma^* reaction at high energies, in the aim of detecting the BFKL Pomeron signals, are briefly introduced. The importance of the NLO QCD corrections to the Photon Impact Factor…
We calculate exclusive vector meson photoproduction within the Color Glass Condensate framework in high-energy photon-nucleus scattering probed experimentally in ultra peripheral heavy ion collisions at RHIC and at the LHC. When the free…
We discuss the relevance of a dedicated measurement of exclusive production of a pair of neutral pions in a hard gamma* gamma scattering at small momentum transfer. In this case, the virtuality of one photon provides us with a hard scale in…
We compute in next-to-leading order (NLO) perturbative QCD the transverse energy carried into the central rapidity unit of hadron or nuclear collisions by the partons freed in the few-GeV subcollisions. The formulation is based on a…
We present a fully differential computation of $e^+\,e^-\to\gamma\,\gamma$ at next-to-next-to-leading order in QED. The process has been implemented into McMule, completing its set of next-to-next-to-leading-order calculations for the most…
The first measurement of $\phi(1020)$ meson production in fixed-target $p$Ne collisions at $\sqrt{s_{NN}}=68.5$ GeV is presented. The $\phi(1020)$ mesons are reconstructed in their $K^{+}K^{-}$ decay in a data sample consisting of proton…
We provide a universal expression of cross sections for the exclusive vector meson production and Deeply Virtual Compton Scattering (DVCS) in photon-proton and photon-nucleus interactions based on the geometric scaling phenomenon. The…
We present the first calculation of direct photon production at next-to-next-to leading order (NNLO) accuracy in QCD. For this process, although the final state cuts mandate only the presence of a single electroweak boson, the underlying…