Neutron Structure Functions From Nuclear Data

The spin-averaged structure function of the neutron, F n 2 , is extracted from recent deuteron data, taking into account the small but significant corrections from nuclear effects in the deuteron. At small x, the F D 2 /F p 2 ratio measured by the New Muon and Fermilab E665 Collaborations is interpreted to suggest a small amount of shadowing in deuterium, which acts to enhance F n 2 for x < ∼ 0.1. A careful treatment of Fermi motion, binding and nucleon off-shell effects in the deuteron also indicates that the neutron/proton structure functio ratio as x → 1 is consistent with the perturbative QCD expectation of 3/7, but larger than the traditional value of 1/4.