Related papers: HERA Diffractive Structure Function Data and Parto…
The kinematic region covered by the LHC experiments probes low values of Bjorken-$x$. At the scale relevant for $W$ and $Z$ production the central rapidity region covers $10^{-3} < x < 10^{-1}$. This means that it is the HERA data which…
The cross section and the proton structure function F2 for neutral current deep inelastic e+p scattering have been measured with the ZEUS detector at HERA using an integrated luminosity of 30 pb-1. The data were collected in 1996 and 1997…
After fifteen years of running and a further five years of analysis, the final inclusive deep inelastic scattering cross sections from H1 and ZEUS have been published. Measurements of neutral current and charged current processes in ep…
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…
This contribution presents recent ZEUS results on proton structure functions at HERA. The inclusive phi(1020)-meson cross section was measured, and it was used to determine the s-quark content of the proton. The structure function F_2 was…
This contribution covers three recent results on deep-inelastic scattering at HERA: (i) new measurements of the proton longitudinal structure function $F_L$ from H1 and ZEUS experiments, (ii) a dedicated NC cross section measurement from…
Results on diffractive scattering observed at HERA and at the TEVATRON are reviewed. This includes the extraction of diffractive parton density functions and determination of the rapidity gap survival probability at HERA and the observation…
We discuss whether the diffractive structure functions defined by current experiments at HERA are indeed probing the partonic structure function of the pomeron. We observe that the {\it pseudorapidity} cuts commonly employed require that…
The measurement and QCD analysis of neutral and charged current cross sections at HERA are presented. For the kinematic range of four-momentum transfer Q^2 between approx. 1 GeV^2 and 30000 GeV^2 and Bjorken x between 0.0013 and 0.65 the…
We study a twist decomposition of diffractive structure functions in the diffractive deep inelastic scattering at HERA. At low $Q^2$ and at large energy the data exhibit a strong deviation from the twist-2 NLO DGLAP description. It is found…
Recent results on diffraction at HERA are presented, focusing on the measurement of the inclusive diffractive cross section and on the study of two and three jets in diffractive ep scattering.
We examine the latest HERA experimental measurements of the $Q^2$ logarithmic derivative of the proton structure function. We analyze the characteristics of DGLAP with and without screening, as well as a Regge type model, and compare their…
These notes are a summary of our efforts to answer the question in the title. Our answer is in the affirmative as: (i) HERA data indicate a large value of the gluon structure function; (ii) no contradictions with the asymptotic predictions…
We present measurements of the structure function \Ft\ in $e^+p$ scattering at HERA in the range $3.5\;\Gevsq < \qsd < 5000\;\Gevsq$. A new reconstruction method has allowed a significant improvement in the resolution of the kinematic…
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…
Many explanations for the excess high-Q^2 $e^+p \to e^+X$ events from H1 and ZEUS at HERA have been proposed each with criticisms. We propose a new method to distinguish different models by looking at a new distribution which is insensitive…
The goal of this study is to determine a set of diffractive parton distribution function (diffractive PDFs) from a QCD analysis of all available and up-to-date diffractive deep inelastic scattering (diffractive DIS) data sets from HERA $ep$…
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…
We pursue the hypothesis that the events with a large rapidity gap, observed at HERA, reflect the scattering of electrons off lumps of wee partons inside the proton. A simple scaling behaviour is predicted for the diffractive structure…
We review topical results on diffractive processes from the experiments H1 and ZEUS at the HERA electron-proton collider. Emphasis is placed on the phenomenological and experimental consequences of the discoveries at HERA for the proposed…