For the first time, beatwave simulations relevant to the UCLA experiment (University of California at Los Angeles) [see Clayton et al., Phys. Rev. Lett. 70, 37 (1993), and also Phys. Plasmas 1, 1753 (1994)] have been made with a relativistic Eulerian Hilbert–Vlasov code for a realistically high ratio of driver frequency to plasma wave frequency (ω0/ωp≊30). Some of the more striking features that have emerged from the Hilbert–Vlasov simulations are discussed in this paper, with particular emphasis on particle dynamics in phase space with beam injection, and action transfer results obtained from the derivation of the integrated Manley–Rowe relations derived for a finite causal system.