The Local Interstellar Ultraviolet Radiation Field

I have used the Hipparcos Input Catalog, together with Kurucz model stellaratmospheres, and information on the strength of the interstellar extinction, tocreate a model of the expected intensity and spectral distribution of the localinterstellar ultraviolet radiation field, under various assumptions concerningthe albedo a of the interstellar grains. (This ultraviolet radiation field isof particular interest because of the fact that ultraviolet radiation iscapable of profoundly affecting the chemistry of the interstellar medium.) Bycomparing my models with the observations, I am able to conclude that thealbedo a of the interstellar grains in the far ultraviolet is very low, perhapsa = 0.1. I also advance arguments that my present determination of this albedois much more reliable than any of the many previous (and conflicting)ultraviolet interstellar grain albedo determinations. Beyond this, I show thatthe ultraviolet background radiation that is observed at high galacticlatitudes must be extragalactic in origin, as it cannot be backscatter of theinterstellar radiation field.