Parton distributions incorporating QED contributions
Abstract
We perform a global parton analysis of deep inelastic and related hardscattering data, including {{mathcal{O}}}(α_QED) corrections to the parton evolution. Although the quality of the fit is essentially unchanged, there are two important physical consequences. First, the different DGLAP evolution of u and d type quarks introduces isospin violation, i.e. u^p neq d^n, which is found to be unambiguously in the direction to reduce the NuTeV sin^2θ_W anomaly. A second consequence is the appearance of photon parton distributions γ(x,Q^2) of the proton and the neutron. In principle these can be measured at HERA via the deep inelastic scattering processes e N to eγ X; our predictions are in agreement with the present data.
 Publication:

European Physical Journal C
 Pub Date:
 February 2005
 DOI:
 10.1140/epjc/s2004020887
 arXiv:
 arXiv:hepph/0411040
 Bibcode:
 2005EPJC...39..155M
 Keywords:

 High Energy Physics  Phenomenology
 EPrint:
 14 pages, 5 figures