Dust Scattered Radiation in the Galactic Poles

Abstract

We have modeled the diffuse background at the Galactic Poles in the far-ultraviolet (FUV: 1536 \AA) and the near-ultraviolet (NUV: 2316 \AA). The background is well-fit using a single-scattering dust model with an offset representing the extragalactic light plus any other contribution to the diffuse background. We have found a dust albedo of 0.35 -- 0.40 (FUV) and 0.11 -- 0.19 in the NGP ($b > 70^{\circ}$) and 0.46 -- 0.56 (FUV) and 0.31 -- 0.33 (NUV) in the SGP ($b < 70^{\circ}$. The differences in the albedo may reflect changes in the dust-to-gas ratio over the sky or in the dust distribution. We find offsets at zero-reddening of 273 -- 286 and 553 -- 581 photons cm$^{-2}$ s$^{-1}$ sr$^{-1}$ \AA$^{-1}$ in the FUV and NUV, respectively, in the NGP with similar values in the SGP.