VLT/SINFONI study of black hole growth in high-redshift radio-loud quasars from the CARLA survey

Abstract

We present VLT/SINFONI observations of 35 quasars at 2.1 < z < 3.2, the majority of which were selected from the Clusters Around Radio-Loud AGN (CARLA) survey. CARLA quasars have large C iv-based black hole masses (M BH > 10 9 M ) and powerful radio emission (P 500 MHz > 27.5 W Hz −1 ). We estimate Hα-based M BH , finding a scatter of 0.35 dex compared to C iv. We evaluate several recipes for correcting C iv-based masses, which reduce the scatter to 0.24 dex. The radio power of the radio-loud quasars is at most weakly correlated with the interconnected quantities Hα-width, L 5100 and M BH , suggesting that it is governed by different physical processes. However, we do find a strong inverse correlation between C iv blueshift and radio power linked to higher Eddington ratios and L 5100 . Under standard assumptions, the BH growth time is longer than the cosmic age for many CARLA quasars, suggesting that they must have experienced more efficient growth in the past. If these BHs were growing from seeds since the epoch of reionization, it is possible that they grew at the Eddington limit like the quasars at z ∼ 6 − 7, and then continued to grow at the reduced rates observed until z ∼ 2 − 3. Finally, we study the relation between M BH and environment, finding a weak positive correlation between M BH and galaxy density measured by CARLA.

Optical Singly-Ionized Iron Emission in Radio-Quiet and Relativistically Jetted Active Galactic Nuclei

“…Their optical spectra can be of both type 1 and type 2 AGN. I Zw 1 is however not a very extreme object: the most extreme accretors show spectra similar to the one of PHL 1092 [86]. Note that the equivalent width is increased, as shown in Figures 11 and A2 but, since there is a corresponding increase in Hβ, the R FeII is left unaffected.…”

Conditions for direct black hole seed collapse near a radio-loud quasar 1 Gyr after the Big Bang

“…The slightly longer cosmic times available to quasars at z 6 make it significantly "easier" to go from a 100 M seed to a SMBH of a few times 10 9 M compared to the quasars at z 7 (e.g., Bañados et al 2018b;Marinello et al 2020;Pacucci & Loeb 2021). For example, assuming constant accretion with Eddington ratios of 0.8-1.3 onto a seed formed at z f = 20 − 10 is able to produce a SMBH like that in J0836 by z = 5.82, while the quasar ULAS J1342+0928 at z = 7.54 requires the existence of a >1000 M seed as early as z = 45 assuming standard Eddington rate accretion (Bañados et al 2018b).…”

Past, present and Future of the Scaling Relations of Galaxies and Active Galactic Nuclei

“…For z>4, M BH estimates historically rely on the CIVλ1549 high-ionization line, and the highest-z sources appear almost always high-accretors [666,667]. The source of concern is that high-ionization lines such as CIVλ1549 are subject to a considerable broadening and blueshifts associated with outflow motions already at low redshift [668,669,670,671]. Overestimates of the virial broadening by a factor as large as 5 -10 [672, 673, 674, 675] for SMBHs at high z may pose a spurious challenge to concordance cosmology [676] and lead to erroneous inferences on the properties of the seed BHs believed to be fledgling precursors of massive BHs.…”