A quasar-galaxy mixing diagram: quasar spectral energy distribution shapes in the optical to near-infrared

作者：Hao Heng^*; Elvis Martin; Bongiorno Angela; Zamorani Gianni; Merloni Andrea; Kelly Brandon C; Civano Francesca; Celotti Annalisa; Ho Luis C; Jahnke Knud; Comastri Andrea; Trump Jonathan R; Mainieri Vincenzo; Salvato Mara; Brusa Marcella; Impey Chris D; Koekemoer Anton M; Lanzuisi Giorgio; Vignali Cristian; Silverman John D; Urry C Megan; Schawinski Kevin

来源：Monthly Notices of the Royal Astronomical Society, 2013, 434(4): 3104-3121.

DOI：10.1093/mnras/stt1228

• surveys - galaxies: evolution
• quasars: general

We define a quasar-galaxy mixing diagram using the slopes of their spectral energy distributions (SEDs) from 1 mu m to 3000 A and from 1 to 3 mu m in the rest frame. The mixing diagram can easily distinguish among quasar-dominated, galaxy-dominated and reddening-dominated SED shapes. By studying the position of the 413 XMM-selected type 1 AGN in the wide-field %26apos;Cosmic Evolution Survey%26apos; in the mixing diagram, we find that a combination of the Elvis et al. mean quasar SED with various contributions from galaxy emission and some dust reddening is remarkably effective in describing the SED shape from 0.3 to 3 mu m for large ranges of redshift, luminosity, black hole mass and Eddington ratio of type 1 AGN. In particular, the location in the mixing diagram of the highest luminosity AGN is very close (within 1 Sigma) to that of the Elvis et al. SED template. The mixing diagram can also be used to estimate the host galaxy fraction and reddening in quasar. We also show examples of some outliers which might be AGN in different evolutionary stages compared to the majority of AGN in the quasar-host galaxy co-evolution cycle.

• 出版日期2013-10