Related papers: Experimental Review of Photon Structure Function D…
The proton structure function F2 has been measured in the range 0.045 GeV2 < Q2 < 0.65 GeV2 and 6*10**-7 < x < 1*10**-3 using 3.9 pb-1 of ep->eX reactions recorded with the ZEUS detector in 1997. The analysis is based on data from the Beam…
The production of final state photons in hadronic $Z$-boson decays can be used to study the quark-to-photon fragmentation function $D_{q\to \gamma}(z,\mu_{F})$. Currently, two different observables are used at LEP to probe this function:…
The spin-averaged structure function of the neutron, F_2^n, is extracted from recent deuteron data, taking into account the small but significant corrections due to nuclear effects in the deuteron. At small x, the F_2D/F_2p ratio measured…
A new measurement of the proton structure function $F_2(x,Q^2)$ is reported for momentum transfers squared $Q^2$ between 1.5 GeV$^2$ and 5000 GeV$^2$ and for Bjorken $x$ between $3\cdot 10^{-5}$ and 0.32 using data collected by the HERA…
Polarized photon structure can be studied in the future polarized $e^{+}e^{-}$ colliding-beam experiments. We investigate the spin-dependent structure function of the virtual photon $g_1^{\gamma}(x,Q^2,P^2)$, in perturbative QCD for…
In the last year four new parametrizations of the Hadronic Photon Structure Function at Next to Leading Order have appeared. In this talk, I briefly review the main features of three of them: the FFNS_CJK, CJK and AFG.
Partonic structure of constituent quark (or{\it{valon}}) in the Next-to-Leading Order is used to calculate pion structure function. This is a further demonstration of the finding that the constituent quark structure is universal, and once…
A measurement of the proton structure function $F_{\!2}(x,Q^2)$ is reported for momentum transfer squared $Q^2$ between 4.5 $GeV^2$ and 1600 $GeV^2$ and for Bjorken $x$ between $1.8\cdot10^{-4}$ and 0.13 using data collected by the HERA…
A future Electron-Ion Collider (EIC) will deliver luminosities of $10^{33} - 10^{34}$ cm$^{-2}$s$^{-1}$ for collisions of polarized electrons and protons and heavy ions over a wide range of center-of-mass energies (40 $\mathrm{GeV}$ to 145…
Two-photon collisions at the e$^+$e$^-$ colliders allow to investigate the formation and the properties of resonant states in a very clean experimental environment. A remarkable number of new results have been recently obtained giving…
The alternative approach to QCD analysis of the photon structure function $F_2^{\gamma}$ is presented. It differs from the conventional one by the presence of the terms which in conventional approach appear in higher orders. We show that…
We perform an adjust to the most recent structure function data, considering the QCD dipole picture applied to ep scattering. The structure function F2 at small x and intermediate Q2 can be described by the model containing an economical…
An extended version of the Monte Carlo program GALUGA is presented for the computation of two-photon production in $\e^+\e^-$ collisions. Functions implemented for the five $\gamma^\star\gamma^\star$ structure functions now include several…
A partisan review of some of the most important $\gamma\gamma$ channels accessible at LEP 2, with special stress on the measurement of the photon structure function $F_{2}^{\gamma}$ and on associated problems with Monte Carlo modelling.
We discuss in detail the photon structure function beyond the leading logarithm approximation. Of special concern is the factorization scheme and the hadronic input; we show how to naturally absorb large terms due to the MSbar factorization…
In the computation of short-distance cross sections initiated by electrons and photons one can adopt the so-called structure-function approach, in which these particles play formally the same roles as hadrons do in QCD factorisation…
We investigate the photon structure functions at small Bjorken variable $x$ in the framework of the holographic QCD, assuming dominance of the Pomeron exchange. The quasi-real photon structure functions are expressed as convolution of the…
The implications of the positivity constraint on the presently unknown polarized structure function of the photon, $g_1^{\gamma}(x,Q^2)$, are studied in detail. In particular the non-trivial consequences of this constraint,…
The aim of this work is to investigate the simultaneous influence of two-photon effects in quantum electrodynamics (QED) and logarithmic corrections in quantum chromodynamics (QCD) on certain observable experimental quantities (structure…
The shape of the electron is studied using lowest-order perturbation theory. Quantities used to probe the structure of the proton: form factors, generalized parton distributions, transverse densities, Wigner distributions and the angular…