  Modeling an arbitrarily accelerating qubit as an open quantum system, we
derive an exact solution for the pure-dephasing model ($\sigma_z$ coupling)
under arbitrary qubit space-time trajectories, as well as general expressions
for the survival probabilities of finite-length qubits interacting with a
massless scalar field under $\sigma_x$ coupling (an Unruh-DeWitt detector) to
second order. We follow the regularization scheme presented in a previous paper
by S. Schlicht, to allow a finite length quantum detector to couple to the
massless scalar field. We compute the decay rate of the qubit in different
coupling regimes, (pure dephasing, Unruh-DeWitt) and explore the Quantum Zeno
(QZE) and Quantum Anti Zeno Effect (QAZE) as the qubit decoheres under it's
interaction with the environment. We compute results for four example
trajectories: stationary, uniform acceleration, oscillation and circular
orbits.
