2006/03/21 by K. J. Eskola, Kari J Eskola, Hannu Paukkunen +1
Physics and Astronomy · #Anomaly (physics) #DGLAP #Deep inelastic scattering #High-Energy Particle Collisions Research #Nuclear structure #Nucleon #Particle physics theoretical and experimental studies #Parton #Quantum Chromodynamics and Particle Interactions #Quark #Scattering #hep-ph
paper · pdf · doi:10.1088/1126-6708/2006/06/008
published as JHEP0606:008,2006 · 17 pages, 7 figures
arxiv created 2006/03/21 · openalex publication_date 2006/06/06 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
By studying the Paschos-Wolfenstein (PW) ratio of deep inelastic ν\rm Fe and ν\rm Fe scattering cross sections, we show that it should be possible to explain the NuTeV sin 2 θ\rm W anomaly with quite conventional physics, by introducing mutually different nuclear modifications for the valence-u and valence-d quark distributions of the protons in iron. Keeping the EKS98 nuclear modifications for uV+dV as a baseline, we find that some 20-30 % nuclear modifications to the uV and dV distributions account for the change induced in the PW ratio by the NuTeV-suggested increase Δsin 2 θ\rm W=0.005. We show that introduction of such nuclear modifications in uV and dV individually, does not lead into contradiction with the present global DGLAP analyses of the nuclear parton distributions, where deep inelastic lA scattering data and Drell-Yan dilepton data from pA collisions are used as constraints. We thus suggest that the NuTeV result serves as an important further constraint in pinning down the nuclear effects of the bound nucleon PDFs. We also predict that if the NuTeV anomaly is explained by this mechanism, the NOMAD experiment should see an increase in the weak mixing angle quite close to the NuTeV result.