Structure function analysis and ψ, jet, W, Z production -pinning down the gluon

A next-to-leading order structure function analysis of deep inelastic μN and νN scattering data is carried out, and acceptable fits for a range of input gluon distributions are found. Three equally acceptable sets of parton distributions are shown which correspond to gluon distributions which are (1) 'soft', (2) 'hard' and (3) which behave as xG(x) approx. 1/√ x at small x. Set 1, with the 'soft' gluon distribution, is favoured. W, Z and jet production data from the CERN collider are well described but do not distinguish between the sets of structure functions. The precision of the predictions for W and Z cross sections allow the collider measurements to yield information on the number of light neutrinos and the mass of the top quark. Finally, how the gluon distribution at very small x may be directly measured at HERA is discussed. (author)