Kerr metric Killing bundles

Abstract We provide a complete characterization of the metric Killing bundles (or bundles) Kerr geometry. Metric can be generally defined for axially symmetric spacetimes with horizons and, case geometries, are sets black holes ( BHs ) or and naked singularities NSs geometries. Each bundle has an equal limiting photon (orbital) frequency, which defines coincides frequency horizon in extended plane. In this plane each is represented as curve tangent to that represents horizons, thus emerge envelope surfaces bundles. show used establish connection between , providing alternative representation such definition BH horizons. introduce concept inner confinement replicas study possibility detecting their frequencies. characteristic frequencies constraining outer region i.e. detect related horizon, replicas, structures may detectable example from emission spectra spacetimes. With we prove existence orbits orbital It shown observations performed close rotation axis geometry, depending on spin. argue these results could further investigate thermodynamic properties.