  By repeatedly measuring a quantum system, the evolution of the system can be
slowed down (the quantum Zeno effect) or sped up (quantum anti-Zeno effect). We
study these effects for a single two-level system coupled to a collection of
harmonic oscillators. Previously, such systems have been studied in both the
weak and the strong system-environment coupling regimes. In this paper, we
apply a polaron transformation in a manner that allows us to study the quantum
Zeno and anti-Zeno effects for a large variety of system-environment
parameters. Using this approach, we reproduce previous results for the weak and
strong system-environment coupling regimes. Moreover, as long as the
environment is super-Ohmic, we show how our approach can be used to explore
regimes such as the moderate system-environment coupling regime that could not
be investigated before in a straightforward manner.
