The Cosmic Ultraviolet Background at the Galactic Poles

We have used archival GALEX data to separate the cosmic ultraviolet background at the Galactic Poles into two components: the dust scattered light and an offset. We have modeled the dust-scattered light using a single- scattering model finding 1 sigma limits of 0.54 – 0.71 for the albedo (a) and 0.74 – 0.83 for the phase function asymmetry factor (g) at 1530 Å and 0.66 – 0.73 for a and 0.71 – 0.77 for g at 2360 Å, that is, the grains are moderately reflective and highly forward-scattering. The offsets are 277 – 284 photon units at 1530 Å and 513 – 520 photon units at 2360 Å. We have estimated other Galactic and extragalactic contributors to the offset finding that 161 ± 18 photon units is unaccounted for at 1530 Å and 335 ± 38 at 2360 Å. The offsets are constant over these regions with variances of 20 – 30 photon units.