Mid-IR QSO spectral templates

However, in Spitzer Infared Spectrograph (IRS) data, few features are detected in most individual spectra because of typically low signal-to-noise ratios (S/N).

By generating spectral composites from over 180 IRS observations of Sloan Digital Sky Survey broad-line quasars, we boost the S/N and reveal features in the complex spectra that are otherwise lost in the noise. In addition to an overall composite, we generate composites in three different luminosity bins that span the range of 5.6{mu}m luminosities of 10^40^-10^46^ (erg/s). We detect the high-ionization, forbidden emission lines of [SIV], [OIV] and [NeV] {lambda}14um in all templates and PAH features in all but the most luminous template.