相关论文: THE CKMT Model and the Theoretical Description of …
We have studied the nucleon structure functions $F_{iN}^{EM} (x,Q^2);~i=1,2$, by including contributions due to the higher order perturbative QCD effect up to NNLO and the non-perturbative effects due to the kinematical and dynamical higher…
We present a set of formulae to extract the longitudinal deep inelastic structure function $F_L$ from the transverse structure function $F_2$ and its derivative $dF_2/dlnQ^2$ at small $x$. Our expressions are valid for any value of…
A recently published soft Regge Dipole Pomeron model intended for all $x$ and $Q^2$ is proved to give a good agreement with (non fitted) recent HERA data from ZEUS (SVX95) on the protonstructure function $F_2^p(x,Q^2)$ at low $Q^2$ and low…
From the new measurement of F_L at HERA we derive fixed-Q^2 averages <F_L/F_2>. We compare these with bounds which are rigorous in the framework of the standard dipole picture. The bounds are sharpened by including information on the charm…
We present a determination of the parton distribution functions of the proton in which NLO and NNLO fixed-order calculations are supplemented by NLLx small-x resummation. Deep inelastic structure functions are computed consistently at…
Nuclear effects in deep inelastic scattering at low$-x$ are phenomenologically described changing the typical dynamical and/or kinematical scales characterizing the free nucleon case. In a holographic approach, this rescaling is an…
We consider a generalized convolution, linking Structure Functions (SF) $F^N_2$ for nucleons, $F^A_2$ for a physical nucleus and $f^{PN,A}$ for a nucleus, composed of point-nucleons. In order to extract $F_2^n$ we employ data on $F_2^{p,A}$…
We provide compact formulas for the heavy quarks structure functions $F^{q\bar{q}}_{2}(x, Q^{2})$ and $F^{q\bar{q}}_{L}(x, Q^{2})$, with $q = c, b$ and $t$, in $e^{-}p$ interaction with respect to the behavior of the gluon density at the…
We construct a simple two-phase model of the nucleon structure functions valid for both small and large Q^2 and in the broad range of Bjorken x. The model incorporates hadron dominance at small x and Q^2 and parton model at large Q^2. The…
We present the perturbative parts of the structure functions F_2^c and F_L^c for a gluon target having nonzero transverse momentum squared at order \alpha _s. The results of the double convolution (with respect to the Bjorken variable x and…
An explicit model for the proton structure function interpolating between low- (VMD and Regge behavior)and high-$Q^2$ (GLAP evolution) is suggested. The model is fitted to the experimental data in a wide range of the kinematical variables…
New Results on the measurement of the proton structure function F_2(x,Q^2) are reported for momentum transfers squared Q^2 >= 1.5 GeV^2 and Bjorken x >= 3.5 10^{-5} using data collected by the HERA experiments H1 and ZEUS in 1994. F_2…
A solution of the CCFM equation for a description of both the structure function $F_2$ and the cross section of forward jet production as measured by the HERA experiments is obtained on the basis of the parton level Monte Carlo program…
Using all available data on the deep-inelastic cross-sections at HERA at x<0.01, we look for geometric scaling of the form \sigma^{\gamma^*p}(\tau) where the scaling variable \tau behaves alternatively like \log(Q^2)-\lambda Y, as in the…
In the kinematic region of small $x$ and large $Q^2$ in deep inelastic scattering, presently being explored by HERA, we present an analysis of the evolution of the longitudinal structure function $F_L^{p}(x, Q^2)$ in the double scaling…
I investigate the theoretical uncertainties on the predictions for the longitudinal structure function. I compare the predictions using fixed-order perturbative QCD, higher twist corrections, small-x resummations and the dipole picture. I…
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…
Nuclear modification of the structure function $F_3$ is investigated. Although it could be estimated in the medium and large $x$ regions from the nuclear structure function $F_2^A$, it is essentially unknown at small $x$. The nuclear…
Deep inelastic structure functions $F_2^A(x)$ are investigated in a $Q^2$ rescaling model with parton recombination effects. We find that the model can explain experimentally measured $F_2^A(x)$ structure functions reasonably well in the…
Different choices of the renormalisation scale (muren) can be used to describe hard scattering processes with two jets at large transverse momentum in deep-inelastic scattering at HERA by fixed order perturbative QCD calculations. For…