  We canonically quantize the Proca field in the Rindler wedge and compute the
total response rate of a uniformly accelerated current interacting with massive
vector Rindler particles from the Unruh thermal bath. We explicitly verify that
the result obtained is exactly the same as the emission rate of massive vector
particles in the Minkowski vacuum as analyzed by inertial observers. Eventually
our results are interpreted in terms of the interaction of static electrons
coupled to $Z^0$ bosons present in Hawking radiation close to the event horizon
of a black hole.
