Target mass effects in deep-inelastic scattering on the deuteron

We calculate the effects of the target mass on deep-inelastic electron scattering on targets of spin one such as the deuteron, focusing on the novel structure functions that enter. It is important to understand these effects given the recent HERMES measurements of the $b_1(x,Q^2)$ structure function of the deuteron. We also derive the spin-one analogues of the Wandzura-Wilczek relations and discuss possible calculations in lattice QCD.