Related papers: Subprocess Size in Hard Exclusive Scattering
We study the production of heavy quarkonium in association with an additional heavy pair. We argue that important contributions may come from phase space regions where three heavy fermions are separated by relative velocities much lower…
When more than one hadron takes part in a hard process, an extended set of quark distribution and fragmentation functions becomes relevant. In this talk, the derivation of Soffer-like bounds for these functions, in the case of a spin-1/2…
Transition to the reflective scattering mode which has emerged at the highest LHC energy of $\sqrt{s}=13$ TeV results in a relative shrinkage with the energy of the impact parameter region responsible for the inelastic hadron collisions.…
We show that the `orthogonal' characteristics of the observed rapidity gaps and large forward energy flows in deep inelastic scattering at HERA, can be described within a single framework. Our Monte Carlo model is based on perturbative QCD…
Central heavy-ion collisions may induce sizeable fluctuations of the topological charge. This effect is expected to distort the dispersion relation for the hadron masses. We construct a general setup for a compact description of this…
We apply the target rest frame formalism to photon + heavy quark production cross section in hadronic collisions at high energies. We investigate the dependence of the production cross section on the photon and quark rapidities and…
At very high energies or small values of Bjorken x, the density of partons, per unit transverse area, in hadronic wavefunctions becomes very large leading to a saturation of partonic distributions. When the scale corresponding to the…
We study eta_c and J/psi hadroproduction induced by multiple scattering off fixed centres in the target. We determine the minimum number of hard scatterings required and show that additional soft scatterings may be factorized, at the level…
A fundamental question in QCD is the non-perturbative structure of hadrons at the amplitude level--not just the single-particle flavor, momentum, and helicity distributions of the quark constituents, but also the multi-quark, gluonic, and…
The high energy limit of QCD is controlled by the small-$x$ part of a hadron wavefunction. We argue that this part is universal to all hadrons and is composed of a new form of matter: a Colored Glass Condensate. This matter is weakly…
In hadron interactions at the LHC energies, the reflective scattering mode starts to play a role which is expected to be even a more significant beyond the energies of the LHC. This new but still arguable phenomenon implies a peripheral…
Recently, the CMS Collaboration has published identified particle transverse momentum spectra in high multiplicity events at LHC energies $\sqrt s $ = 0.9-13 TeV. In the present work the transverse momentum spectra have been analyzed in the…
In these lectures, I survey a number of applications of light-front methods to hadron and nuclear physics phenomenology and dynamics, Light-front Fock-state wavefunctions provide a frame-independent representation of hadrons in terms of…
Heavy quarks provide a new dimension to QCD, allowing tests of fundamental theory, the nature of color confinement, and the production of new exotic multiquark states. I also discuss novel explanations for several apparently anomalous…
As a consequence of QCD factorization theorems, a wide variety of inclusive and exclusive cross sections may be formulated in terms of a universal colour dipole cross section at small $x$. It is well known that for small transverse size…
As the value of the longitudinal momentum carried by partons in a ultra-relativistic hadron becomes small, one observes a growth of their density. When the parton density becomes close to a value of order $1/\alpha_s$, it does not grow any…
We suggest that the large single spin asymmetries observed at high momentum fractions x_F and transverse momenta k_T of the pion in p^\uparrow p -> \pi(x_F,k_T)+X arise from the coherence of the soft interactions with the hard parton…
We summarize our understanding of the dynamical mechanisms governing rapidity gap survival in central exclusive diffraction, pp -> p + H + p (H = high-mass system), and discuss the uncertainties in present estimates of the survival…
We investigate the scattering of a quark on a heavy nucleus at high energies using the time-dependent basis light-front quantization (tBLFQ) formalism, which is the first application of the tBLFQ formalism in QCD. We present the real-time…
The probabilistic model of parton distributions, previously developed by one of the authors, is generalized to include the transversity distribution. When interference effects are attributed to quark level only, the intrinsic quark motion…