Jul 16 – 22, 2009
Kraków, Poland
Europe/Warsaw timezone

Measurement of the Inclusive ep Scattering Cross Section at Low and Medium Q^2 at HERA

Jul 16, 2009, 4:45 PM
Exhibition room A (Kraków, Poland)

Exhibition room A

Kraków, Poland

The Auditorium Maximum of the Jagiellonian University 33 Krupnicza Street 31-123 Kraków
QCD at Colliders V. QCD at Colliders


Jan Kretzschmar (University of Liverpool)


Measurements of the inclusive ep scattering cross section are presented in the region of low to medium momentum transfers, 0.2 GeV^2 < Q^2 < 150 GeV^2, and Bjorken x, 5x10^-6 < x < 0.1. The results are based on data sets collected by the H1 Collaboration at HERA at positron beam energies of 27.6 GeV and proton beam energies of 820 or 920 GeV. A combination with data previously published by H1 leads to a cross section measurement of a few percent accuracy at low Q^2 and 1.3-2% at medium Q^2. A kinematic reconstruction method exploiting radiative ep events extends the measurement to lower Q^2 and larger x. The low Q^2 data are compared with theoretical models which apply to the transition region from photoproduction to deep inelastic scattering. A next-to-leading order QCD analysis is performed on the data with sufficiently high Q^2 to determine the parton distributions in the proton.

Primary author


Jan Kretzschmar (University of Liverpool)

Presentation materials