  In March 2018, Mukherjee (2018) reported the detection by VERITAS of
very-high-energy emission (VHE; > 100 GeV) from 3C 264. This is the sixth, and
second most distant, radio galaxy ever detected in the TeV regime. In this
article we present a radio and X-ray analysis of the jet in 3C 264. We
determine the main physical parameters of the parsec-scale flow and explore the
implications of the inferred kinematic structure for radiative models of this
gamma-ray emitting jet. The radio data set is comprised of VLBI observations at
15 GHz from the MOJAVE program, and cover a time period of ~2 years. Through a
segmented wavelet decomposition method we estimate the apparent displacement of
individual plasma features; we then perform a pixel-based analysis of the
stacked image to determine the jet shape. The X-ray data set includes all
available observations from the Chandra, XMM, and Swift satellites, and is
used, together with archival data in the other bands, to build the SED. Proper
motion is mostly detected along the edges of the flow, which appears strongly
limb-brightened. The apparent speeds increase as a function of distance from
the core up to a maximum of ~$11.5$ c. This constrains the jet viewing angle to
assume relatively small values ($\theta\lesssim10^{\circ}$). In the
acceleration region, extending up to a de-projected distance of
~$4.8\times10^4$ Schwarzschild radii (~$11$ pc), the jet is collimating
($r\propto z^{0.40\pm 0.04}$), as predicted for a magnetically-driven plasma
flow. By assuming that the core region is indeed magnetically dominated
($U_B/U_e>1$), the SED and the jet power can be well reproduced in the
framework of leptonic models, provided that the high-energy component is
associated to a second emitting region. The possibility that this region is
located at the end of the acceleration zone, either in the jet layer or in the
spine, is explored in the modeling.
