Related papers: High energy factorization predictions for the char…
At low Q^2, charm production in deep-inelastic scattering is adequately described by assuming generation in electroweak boson-light parton scattering (dominantly boson-gluon fusion) which naturally incorporates the correct threshold…
We argue that the difference between the structure functions corresponding to deep inelastic scattering with and without heavy quarks in the current fragmentation region scales at high $Q^2$ and fixed (low) $x_{Bj}$. The lower bound on…
The proton diffractive structure function $F_2^{D(3)}$ measured in the H1 and ZEUS experiments at HERA is analyzed in terms of both Regge phenomenology and perturbative QCD evolution. A new method determines the values of the Regge…
We revisit the calculation of multiple parton scattering of a heavy quark in nuclei within the framework of recently improved high-twist factorization formalism, in which gauge invariance is ensured by a delicate setup of the initial…
An overview of recent measurements of charm and beauty production in ep collisions at HERA is presented. Various techniques are used by the ZEUS and H1 collaborations to efficiently tag heavy quarks in events and different regions of phase…
We develop the pQCD description of diffraction excitation of heavy flavours in DIS and we derive the analytic formulas for the mass spectrum in leading log$m_f^{2}$. The result illustrates nicely non-factorization properties of the QCD…
In the semiclassical approach, inclusive and diffractive quark and gluon distributions are expressed in terms of correlation functions of Wilson loops. Each Wilson loop integrates the colour field strength in the area between the…
Inclusive production of D* mesons in deep-inelastic ep scattering at HERA is studied in the range 5 < Q^2 <100 GeV^2 of the photon virtuality and 0.02 < y < 0.7 of the inelasticity of the scattering process. The observed phase space for the…
On the basis of some peculiar scaling properties of the OPE coefficient functions, we give the lower bounds for F_2^{c\bar{c}} and F_2^{b\bar{b}} independently of the properties of the gluon density function. Predictions for F_2^{b\bar{b}}…
We present microscopic QCD calculation of the cross section of diffractive DIS and of the partonic structure of the pomeron from the dipole approach to the generalized BFKL pomeron. We show that the pomeron can not be treated as a particle…
The QCD factorization theorem for diffractive processes in DIS is used to derive formulae for the leading twist contribution to the nuclear shadowing of parton distributions in the low thickness limit. Based on the current analyzes of…
In the framework of the semi-hard ($k_t-$factorization) approach, we analyze the various charm production processes in the kinematic region covered by the HERA experiments
Recent results from the experiments ZEUS and H1 on charm production in $ep$ collisions are reviewed. The topics are elastic and inelastic $J/\psi$ photoproduction, $D^*$ photoproduction differential cross sections and a first look at the…
Previous work on electroweak radiative corrections to high energy scattering using soft-collinear effective theory (SCET) has been extended to include external transverse and longitudinal gauge bosons and Higgs bosons. This allows one to…
Higher twist effects in the deeply inelastic scattering are studied. We start with a short review of the theoretical results on higher twists in QCD. Within the saturation model we perform a twist analysis of the nucleon structure functions…
We derive a high energy factorization theorem for inclusive gluon production in A+A collisions. Our factorized formula resums i) all order leading logarithms (g^2 \ln(1/x_{1,2}))^n of the incoming partons momentum fractions, and ii) all…
The proton structure function $F_2^p(x,Q^2)$ is described in the framework of the off-shell extention of the Regge-eikonal approach which automatically takes into account off-shell unitarity. We achieved a good quality of description for…
We perform the first complete one-loop study of exclusive photoproduction of vector quarkonia off protons in Collinear Factorisation (CF) including the scale evolution of the Generalised Parton Distributions (GPDs). We confirm the…
The currently operating FASER experiment and the planned Forward Physics Facility (FPF) will detect a large number of neutrinos produced in proton-proton collisions at the LHC. In this work, we estimate neutrino fluxes at these detectors…
We discuss the polarised fragmentation functions of quarks and gluons in Perturbative Quantum Chromodynamics. The Altarelli-Parisi evolution equations governing these fragmentation functions are presented. We find that the first moment of…