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arXiv · 1404.1080

Rapidly growing black holes and host galaxies in the distant Universe from the Herschel Radio Galaxy Evolution Project

G. Drouart·C. De Breuck·J. Vernet·N. Seymour·M. Lehnert·P. Barthel·F. E. Bauer·E. Ibar·A. Galametz·M. Haas·N. Hatch·J. R. Mullaney·N. Nesvadba·B. Rocca-Volmerange·H. J. A. Rottgering·D. Stern·D. Wylezalek
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Abstract

We present results from a survey of 70 radio galaxies (RGs) at redshifts 1 2.5 are higher than the sSFR of typical star-forming galaxies over the same redshift range but are similar or perhaps lower than the galaxy population for RGs at z<2.5. By comparing the sSFR and the specific black hole mass accretion rate, we conclude that BHs in radio loud AGN are already, or soon will be, overly massive compared to their host galaxies in terms of expectations from the local MBH-MGal relation. In order to ``catch up'' with the BH, the galaxies require about an order-of magnitude more time to grow in mass, at the observed SFRs, compared to the time the BH is actively accreting. However, during the current cycle of activity, we argue that this catching-up is likely to be difficult due to the short gas depletion times. Finally, we speculate on how the host galaxies might grow sufficiently in stellar mass to ultimately fall onto the local MBH-MGal relation.

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G. Drouart, C. De Breuck, J. Vernet, N. Seymour, M. Lehnert, P. Barthel, F. E. Bauer, E. Ibar, A. Galametz, M. Haas, N. Hatch, J. R. Mullaney, N. Nesvadba, B. Rocca-Volmerange, H. J. A. Rottgering, D. Stern, D. Wylezalek. 2014-04-03. Rapidly growing black holes and host galaxies in the distant Universe from the Herschel Radio Galaxy Evolution Project. https://doi.org/10.1051/0004-6361/201323310

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