Measurement of the neutron and the proton F2 structure function ratio

Abstract The ratio of the structure function F 2 n / F 2 p ( x ) has been measured in deep inelastic scattering of 274 GeV muons on hydrogen and deuterium targets exposed simultaneously to the beam. The results were obtained from 0.3 (0.6) million events from hydrogen (deuterium) in the range 0.004 x Q 2 2 . At x σ w / σ z production cross section ratio in p p collisions are discussed. When compared to other results obtained at lower energies, the data indicate a Q 2 dependence of the ratio.