Related papers: Applications of quark-hadron duality in F2 structu…
We investigate the evolution of parton densities at small values of the momentum fraction, x, by including resummed anomalous dimensions in the renormalization group equations. The resummation takes into account the leading-logarithmic…
A detailed analysis is presented of the diffractive deep-inelastic scattering process $ep\to eXY$, where $Y$ is a proton or a low mass proton excitation carrying a fraction $1 - \xpom > 0.95$ of the incident proton longitudinal momentum and…
We recall our recent description of quark parton densities of the proton at $Q^2=4 GeV^2$ in terms of Fermi-Dirac distributions parametrized with very few free parameters. We have also proposed some simple assumptions to relate unpolarized…
Parton distribution functions (PDFs) with QED corrections extracted from the QED$\otimes$QCD DGLAP evolution equations in the framework of "valon" model. Our results for the PDFs with QED corrections in this phenomenological model are in…
We study lifetimes of heavy mesons in the 't Hooft model, a large-$N_c$ theory of strong interaction in two-dimensional spacetime. Since this model is solvable, one can evaluate the total decay widths through hadronic amplitudes that are…
To study the heavy quark production processes, we use the transverse momentum dependent (TMD, or unintegrated) gluon distribution function in a proton obtained recently using the Kimber-Martin-Ryskin prescription from the Bessel-inspired…
Data from H1 and ZEUS on the structure and the quark and gluon densities of the proton are discussed. A brief excursion is made into the field of inclusive diffraction by deep inelastic scattering. The comparison of e- p and e+ p scattering…
The reduced cross sections for ep deep inelastic scattering have been measured with the ZEUS detector at HERA at three different centre-of-mass energies, 318, 251 and 225 GeV. From the cross sections, measured double differentially in…
We present an elementary introduction to the problem of quark-hadron duality and its practical limitations, in particular as it concerns local duality violation in inclusive B meson decays. We show that the accurate definition of duality…
We discuss the determination of electroweak parameters from hadron collider observables, focusing on the $W$ boson mass measurement. We revise the procedures adopted in the literature to include in the experimental analysis the uncertainty…
We investigate the systematic uncertainties and potential biases arising from the inclusion of large-$x$ corrections to proton and deuteron deep inelastic scattering (DIS) data in global quantum chromodynamics (QCD) analyses. Using the…
We analyze the impact of the recent HERA run I+II combination of inclusive deep inelastic scattering cross-section data on the CT14 global analysis of PDFs. New PDFs at NLO and NNLO, called CT14$_{\textrm{HERA2}}$, are obtained by a refit…
Structure function data together with other measurements from fixed-target deep inelastic scattering and hadron-hadron collider experiments which contribute to our knowledge of the parton density functions are reviewed. The inclusive…
The cross section of inclusive diffractive process ep -> eXp was measured within a wide kinematic range in the H1 and ZEUS experiments at HERA. Results obtained by different experiments and methods are compatible within measurement…
The electron-proton collider HERA allows the study of the partonic content of the proton in regions of Q-squared up to 50,000 GeV$^2$ and values of Bjorken-x down to 10^-5. This paper presents recent precision measurements of structure…
Measurements of the proton structure function $F_2$ in the $Q^2$ range $0.6 - 17 \rm GeV^2$ from ZEUS 1995 shifted vertex data and $Q^2 \simeq 1.5 - 20000 \rm GeV^2$ from 1996 and 1997 ZEUS data are presented. From the former and other ZEUS…
We extract the ratio of the down (d) and up (u) parton distribution functions (PDF's) from the ratio of deuteron and proton structure function F_2(d)/F_2(p) measured by NMC. We use corrections for nuclear binding effects in the deuteron,…
Results from the HERA experiments, H1 and ZEUS, on $e^\pm p$ deep inelastic scattering (DIS) provide an important contribution to the knowledge of the proton structure and QCD. The data were collected in the years 1994-2000 (HERA I) and…
Recent structure function results from H1 and ZEUS are presented. The data have been recorded in e+p and e-p collisions for both Neutral Current and Charged Current reactions, covering a wide kinematic range of squared four-momentum…
QCD-based scaling arguments predict the predominance of longitudinal over transverse electroproduction of pions by terms $\propto Q^2$. However, data from JLAB, Cornell and DESY, covering a wide kinematical range $1 < Q^2 < 11\, {\rm…