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arXiv · hep-ex/0512060

First Measurement of Charged Current Cross Sections at HERA with Longitudinally Polarised Positrons

H1 Collaboration
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Abstract

Data taken with positrons of different longitudinal polarisation states in collision with unpolarised protons at HERA are used to measure the total cross sections of the charged current process, e^+ p \to \barνX, for negative four-momentum transfer squared Q^2 > 400 GeV^2 and inelasticity y<0.9. Together with the corresponding cross section obtained from the previously published unpolarised data, the polarisation dependence of the charged current cross section is measured for the first time at high Q^2 and found to be in agreement with the Standard Model prediction.

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H1 Collaboration. 2005-12-22. First Measurement of Charged Current Cross Sections at HERA with Longitudinally Polarised Positrons. https://doi.org/10.1016/j.physletb.2006.01.054

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