https://doi.org/10.1140/epjc/s2004-02088-7
theoretical physics
Parton distributions incorporating QED contributions
1
Institute for Particle Physics Phenomenology, University of Durham, DH1 3LE, UK
2
Rutherford Appleton Laboratory, OX11 0QX, Chilton, Didcot, Oxon, UK
3
Cavendish Laboratory, University of Cambridge, Madingley Road, CB3 0HE, Cambridge, UK
* e-mail: thorne@hep.phy.cam.ac.uk
We perform a global parton analysis of deep inelastic and related hard-scattering data, including 
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. 
, which is found to be unambiguously in the direction to reduce the NuTeV 
anomaly. A second consequence is the appearance of photon parton distributions 
of the proton and the neutron. In principle these can be measured at HERA via the deep inelastic scattering processes 
; our predictions are in agreement with the present data.
© Springer-Verlag, 2005
