Gauge Boson Signals at the Cosmological Collider
  We study the production of massive gauge bosons during inflation from the
axion-type coupling to the inflaton and the corresponding oscillatory features
in the primordial non-Gaussianity. In a window in which both the gauge boson
mass and the chemical potential are large, the signal is potentially reachable
by near-future large scale structure probes. This scenario covers a new region
in oscillation frequency which is not populated by previously known
cosmological collider models. We also demonstrate how to properly include the
exponential factor and discuss the subtleties in obtaining power dependence of
the gauge boson mass in the signal estimate.
