Measurement and QCD Analysis of Neutral and Charged Current Cross Sections at HERA

TL;DR

This paper presents measurements of neutral and charged current cross sections at HERA, extending the analysis to high inelasticity and Q^2, and performs QCD fits to extract parton distributions using new and existing data.

Contribution

It provides new measurements of structure functions and cross sections at high Q^2, and conducts updated QCD analyses to determine flavor-separated parton distributions.

Findings

Determined the longitudinal structure function F_L at high Q^2.

Measured the structure function x F_3 using combined e^+ p and e^- p data.

Performed new QCD fits to extract parton distribution functions.

Abstract

The inclusive e^+ p single and double differential cross sections for neutral and charged current processes are measured with the H1 detector at HERA. The data were taken in 1999 and 2000 at a centre-of-mass energy of \sqrt{s} = 319 GeV and correspond to an integrated luminosity of 65.2 pb^-1. The cross sections are measured in the range of four-momentum transfer squared Q^2 between 100 and 30000 GeV^2 and Bjorken x between 0.0013 and 0.65. The neutral current analysis for the new e^+ p data and the earlier e^- p data taken in 1998 and 1999 is extended to small energies of the scattered electron and therefore to higher values of inelasticity y, allowing a determination of the longitudinal structure function F_L at high Q^2 (110 - 700 GeV^2). A new measurement of the structure function x F_3 is obtained using the new e^+ p and previously published e^\pm p neutral current cross section data at high Q^2. These data together with H1 low Q^2 precision data are further used to perform new next-to-leading order QCD analyses in the framework of the Standard Model to extract flavour separated parton distributions in the proton.