Friday, 8 February 2008

Black hole growth and stellar assembly at high-z

Figure 1 in Polletta (2008, arXiv:0802.0693)
The relative luminosities produced by stars (H-band) and by AGN-heated dust (5 um) in three classes of AGNs are compared. The three classes are high-z radio galaxies (HzRGs, blue circles), sub-millimeter detected AGNs (SMG/AGN, green triangles) and IR-selected obscured QSOs (IsOQ, red crosses). The diagonal lines indicate expected luminosities for various black hole masses assuming a variety of values for the Eddington ratio (lambda) and offsets to the local M_bh-M_star relation (delta).

There is a segregation between the luminosities of the three classes, which can be attributed to the different classes of AGNs emitting at different Eddington ratios or that they follow different M_bh-M_star relations. Also evolution from IsOQs to SMG/AGNs is suggested as the bulk of stellar mass is still being assembled in the former, whereas the bulge is at a more advanced stage for the HzRGs and SMG/AGNs hence possibly representing a later phase in AGN evolution.

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