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arXiv · hep-ex/9905032

Measurement of High-Q^2 Neutral-Current e^+p Deep Inelastic Scattering Cross-Sections at HERA

ZEUS Collaboration
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Abstract

The e^+p neutral-current deep inelastic scattering differential cross-sections $dσ/dQ^2$, for Q^2 > 400 GeV^2, $dσ/dx$ and $dσ/dy$, for Q^2 > 400, 2500 and 10000 GeV^2, have been measured with the ZEUS detector at HERA. The data sample of 47.7 pb^-1 was collected at a center-of-mass energy of 300 GeV. The cross-section, $dσ/dQ^2$, falls by six orders of magnitude between Q^2 = 400 and 40000 GeV^2. The predictions of the Standard Model are in very good agreement with the data. Complementing the observations of time-like Z^0 contributions to fermion-antifermion annihilation, the data provide direct evidence for the presence of Z^0 exchange in the space-like region explored by deep inelastic scattering.

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ZEUS Collaboration. 1999-07-07. Measurement of High-Q^2 Neutral-Current e^+p Deep Inelastic Scattering Cross-Sections at HERA. https://doi.org/10.1007/s100520050645

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