A Composite EUV AGN Spectrum and the AGN Contribution to the Low Redshift UV Background

The Far Ultraviolet Spectroscopic Explorer (FUSE) has surveyed a large sample (> 100) of active galactic nuclei (AGN) in the low-redshift universe. Its response at short wavelengths makes it possible to measure directly the EUV spectral shape of QSOs and Seyfert I galaxies at z < 0.3. Using archival FUSE spectra, we form a composite extreme ultraviolet (EUV) spectrum of QSOs at z < 1 and compare it to UV/optical composite spectra of QSOs at higher redshift, particularly the composite spectrum from archival Hubble Space Telescope spectra. We use the FUSE composite spectrum to calculate the AGN contribution to the local ultraviolet background and find a value 70% larger than previous estimates.