Measurement of the Proton Structure Function F_2 and σ_{tot}^{γ^* p} at Low Q^2 and Very Low x at HERA

Abstract

A small electromagnetic sampling calorimeter, installed in the ZEUS experiment in 1995, significantly enhanced the acceptance for very low x and low Q^2 inelastic neutral current scattering, e^{+}p \to e^{+}X, at HERA. A measurement of the proton structure function F_2 and the total virtual photon-proton (γ^*p) cross-section is presented for 0.11 \le Q^{2} \le 0.65 GeV^2 and 2 \times 10^{-6} \le x \le 6 \times 10^{-5}, corresponding to a range in the γ^{*}p c.m. energy of 100 \le W \le 230 GeV. Comparisons with various models are also presented.

18 pages including 4 figures

Cited by in corpus (89)

• Quark Gluon Plasma an Color Glass Condensate at RHIC? The perspective from the BRAHMS experiment
• Saturation Effects in Deep Inelastic Scattering at low $Q^2$ and its Implications on Diffraction
• Combined Measurement and QCD Analysis of the Inclusive ep Scattering Cross Sections at HERA
• Cosmic ray event generator Sibyll 2.1
• Geometric scaling for the total gamma^* p cross section in the low x region
• Evolution of the nuclear modification factors with rapidity and centrality in d+Au collisions at $\sqrt{s_{NN}} = 200 GeV
• Small x: Two Pomerons!
• Non-linear QCD meets data: A global analysis of lepton-proton scattering with running coupling BK evolution
• Leading proton production in deep inelastic scattering at HERA
• Exclusive electroproduction of J/psi mesons at HERA
• A ZEUS next-to-leading-order QCD analysis of data on deep inelastic scattering
• Measurement of the Proton Structure Function F_2 at Very Low Q^2 at HERA
• Measurement of the Inclusive e{\pm}p Scattering Cross Section at High Inelasticity y and of the Structure Function FL
• HERA Collider Physics
• Structure Functions of the Nucleon and their Interpretation
• The Evolution of Unpolarized Singlet Structure Functions at Small x
• Extracting the dipole cross-section from photo- and electro-production total cross-section data
• Leading neutron production in $e^{+}p$ collisions at HERA
• Saturation in Deep Inelastic Scattering from AdS/CFT
• Dissociation of virtual photons in events with a leading proton at HERA
• Small-x behavior of the structure function F_2 and its slope partial ln(F_2)/partial ln(1/x) for "frozen" and analytic strong-coupling constants
• S-Matrix Unitarity, Impact Parameter Profiles, Gluon Saturation and High-Energy Scattering
• A QCD analysis of ZEUS diffractive data
• A Kinematically Complete Measurement of the Proton Structure Function F2 in the Resonance Region and Evaluation of Its Moments
• Anatomy of the differential gluon structure function of the proton from the experimental data on F_2p
• Small x behaviour of parton distributions with soft initial conditions
• Collider Physics at HERA
• Leading proton production in e^+p collisions at HERA
• Small x behavior of parton distributions. A study of higher twist effects
• Unbiased determination of the proton structure function F_2^p with faithful uncertainty estimation
• CTEQ-TEA parton distribution functions and HERA Run I and II combined data
• The effect of screening on the $x$ and $Q^2$ bhaviour of $F_2$ slopes
• Moments of the Proton F2 Structure Function at Low Q2
• Inclusive Measurements of Inelastic Electron and Positron Scattering from Unpolarized Hydrogen and Deuterium Targets
• Renormalon Model Predictions for Power-Corrections to Flavour Singlet Deep Inelastic Structure Functions
• Low-x scaling in ${\gamma }^{\ast }p$ total cross sections
• A Comprehensive Approach to Structure Functions
• A unitary model for structure functions and diffractive production at small x
• QCD effective charge and the structure function $F_2$ at small-$x$
• The Tensor Pomeron and Low-x Deep Inelastic Scattering
• Next-to-Leading Order Constituent Quark Structure and Hadronic Structure Functions
• Deep Inelastic Scattering Data and the Problem of Saturation in Small-x Physics
• High Pt Hadron Spectra at High Rapidity
• Unitarity constraints for DIS off nuclei: predictions for electron-ion colliders
• Rapidity and species dependence of particle production at large transverse momentum for $d$+Au collisions at \sqrt s_NN = 200 GeV
• The BFKL Pomeron in 2+1 Dimensional QCD
• The Q^2 Dependence of Dijet Cross Sections in gamma p Interactions at HERA
• What did HERA teach us about the structure of the proton?
• Deep inelastic scattering at low x: Generalized vector dominance and the color dipole picture
• An Evaluation of The Proton Structure Functions $F_2$ and $F_L$ at Small $x$
• Applications of a nonlinear evolution equation I: the parton distributions in the proton
• Has HERA reached a new QCD regime?
• t-channel unitarity and photon cross sections
• How fast do small x structure function rise ? A comparative analysis
• On the rapidity dependence of the average transverse momentum in hadronic collisions
• The dependence of dijet production on photon virtuality in ep collisions at HERA
• Multiplicity and rapidity dependence of ${\mathrm{K}}^{\ast }(892{)}^0$ and $\varphi (1020)$ production in p-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV
• Bose-Einstein correlations in one and two dimensions in deep inelastic scattering
• Diffractive production and the total cross section in deep inelastic scattering
• Color dipole cross section and inelastic structure function
• Total photoproduction cross-section at very high energy
• QCD effective charges and the structure function $F_2$ at small-$x$: Higher twist effects
• Measurement of D*+- meson production in ep scattering at low Q^2
• Small x behavior of the slope dlnF_2/dln(1/x) in the framework of perturbative QCD
• New extraction of alpha_s(MZ) from proton DIS data
• Spin constraints on Regge predictions and perturbative evolution in high energy collisions
• Phenomenological description of the gamma* p cross section at low Q2
• Implications of HERA results for very high energy cosmic ray physics
• Hard pomeron enhancement of ultrahigh-energy neutrino-nucleon cross-sections
• Non-linear BFKL dynamics: color screening vs. gluon fusion
• A unitarized model of inclusive and diffractive DIS with Q2-evolution
• A Few-Degree Calorimeter for the future Electron-Ion Collider
• The neural network approach to parton distribution functions
• Describing F_2 through a finite sum of gluon ladders
• Critical Correlations of Wilson Lines in SU(3) and the High Energy ${\gamma }^{\ast }p$ Cross Section
• Nuclear structure functions and off-shell corrections
• F_2 at low Q^2
• Global QCD fit from $Q^2=0$ to $Q^2=30000$ GeV${}^2$ with Regge-compatible initial condition
• Gluon Polarization In Nucleon
• Low-x Physics
• Proton Structure Functions from Chiral Dynamics and QCD Constraints
• Unitarized Diffractive Scattering in QCD and Application to Virtual Photon Total Cross Sections
• On a two Pomeron description of the F_2 structure function
• Q2-evolution of parton densities at small-x values
• The ${\gamma }^{\ast }p$ total cross section and elastic diffraction
• Description of elastic vectormeson production and F_2 by two pomerons
• Asymptotic Gluon Shadowing
• Summary of the Structure Function Working Group at DIS'99
• An Investigation of the Hard Contribution to phi Photoproduction