Hierarchy independent sensitivity to leptonic {\delta}_CP with atmospheric neutrinos

The Dirac leptonic CP phase {\delta}_CP is one of the crucial unknown parameters in neutrino oscillation physics. In this paper we explore the possibility of using low energy atmospheric neutrino events to probe {\delta}_CP . We show that at sub GeV energies, when the events are binned as a function of the energy and direction of the final state leptons, a consistent distinction between various true {\delta}_CP values is obtained. We also show that at these energies there is no sensitivity to the mass ordering/hierarchy, so that {\delta}CP can be measured without hierarchy ambiguity. In addition a preliminary \c{hi}^2 analysis of the sensitivity to {\delta}CP using atmospheric neutrinos assuming a generic detector with perfect separation between charged current {\nu}{\mu} , \bar{{\nu}}{\mu} , {\nu}_e and \bar{{\nu}}_e events is given.