Determining the Octant of $\theta_{23}$ at LBNE in conjunction with Reactor Experiments

Abstract

We have explored the possibilities of resolving the $\theta_{23}$ octant degeneracy present in the newly planned Long-Baseline Neutrino Experiment (LBNE) by combining reactor data. Reactor experiments have already measured the third mixing angle $\theta_{13}$ very precisely and this precise measurenent of $\theta_{13}$ in turn helps in $\theta_{23}$ octant measurement. We have examined the octant sensitivity with and without reactor data and it improves if reactor data is added. The comparative study of octant sensitivities of 10kt and 35kt liquid argon Far Detectors, with and without the Near Detector, reveals that the sensitivity increases with an increase in detector mass. Also, the presence of the Near Detector improves the sensitivity. The effect of adding priors on octant determination is also studied in this work.