  Novel low index (n less than 1.3)/high light trapping cladding films
consisting of nanoporous alumina (sapphire), as formed by controlled
anodization of aluminum, are described. These films are mechanically hard,
intrinsically very rad-hard, and have an index of refraction n sufficiently
small to triple the light capture of waveshifting or scintillating fibers and
transparent plastic, glass or quartz core fibers. The low indices enable
light-piping of water Cerenkov light. Applications are in Energy, Intensity,
and Cosmic/Astroparticle detectors.
