First measurement of charged current cross sections at HERA with longitudinally polarised positrons


Aktas A., Andreev V., Anthonis T., Antunovic B., Aplin S., Asmone A., ...More

Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, vol.634, no.2-3, pp.173-179, 2006 (SCI-Expanded) identifier identifier

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→νX, for negative four-momentum transfer squared Q2>400 GeV2 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. © 2006 Elsevier B.V. All rights reserved.