Kavli Affiliate: Robert A. Simcoe
| First 5 Authors: Anna-Christina Eilers, Ruari Mackenzie, Elia Pizzati, Jorryt Matthee, Joseph F. Hennawi
| Summary:
We expect luminous ($M_{1450}lesssim-26.5$) high-redshift quasars to trace
the highest density peaks in the early universe. Here, we present observations
of four $zgtrsim6$ quasar fields using JWST/NIRCam in imaging and widefield
slitless spectroscopy mode and report a wide range in the number of detected
[OIII]-emitting galaxies in the quasars’ environments, ranging between a
density enhancement of $deltaapprox65$ within a $2$ cMpc radius – one of the
largest proto-clusters during the Epoch of Reionization discovered to date – to
a density contrast consistent with zero, indicating the presence of a
UV-luminous quasar in a region comparable to the average density of the
universe. By measuring the two-point cross-correlation function of quasars and
their surrounding galaxies, as well as the galaxy auto-correlation function, we
infer a correlation length of quasars at $langle zrangle=6.25$ of $r_0^{rm
QQ}=22.0^{+3.0}_{-2.9}~{rm cMpc},h^{-1}$, while we obtain a correlation
length of the [OIII]-emitting galaxies of $r_0^{rm GG}=4.1pm0.3~{rm
cMpc},h^{-1}$. By comparing the correlation functions to dark-matter-only
simulations we estimate the minimum mass of the quasars’ host dark matter halos
to be $log_{10}(M_{rm halo, min}/M_odot)=12.43^{+0.13}_{-0.15}$ (and
$log_{10}(M_{rm halo, min}^{rm [OIII]}/M_odot) = 10.56^{+0.05}_{-0.03}$ for
the [OIII]-emitters), indicating that (a) luminous quasars do not necessarily
reside within the most overdense regions in the early universe, and that (b)
the UV-luminous duty cycle of quasar activity at these redshifts is $f_{rm
duty}ll1$. Such short quasar activity timescales challenge our understanding
of early supermassive black hole growth and provide evidence for highly
dust-obscured growth phases or episodic, radiatively inefficient accretion
rates.
| Search Query: ArXiv Query: search_query=au:”Robert A. Simcoe”&id_list=&start=0&max_results=3