The Impact of Sterile eV^2 Neutrinos on CP measurements at Long Baselines

Several experiments have provided tantalizing but inconclusive hints for the presence of a sterile sector with one or more neutrinos having mass-squared differences with the active neutrinos of O(1) ev2. Concurrently, but independently, an aggressive world-wide program of long baseline neutrino physics is being actively pursued to establish the presence of CP violation in the lepton sector. It has been usually assumed that sterile eV2 neutrinos, which manifest themselves via short baseline oscillations, do not significantly impact phenomena and measurements at currently planned long baseline experiments. We examine this assumption and show that their effects can actually be quite large, and may affect the planned CP measurements appreciably.