TY - JOUR
T1 - The clustering of undetected high-redshift black holes and their signatures in cosmic backgrounds
AU - Ricarte, Angelo
AU - Pacucci, Fabio
AU - Cappelluti, Nico
AU - Natarajan, Priyamvada
N1 - Funding Information:
We thank Alexander Kashlinsky for pointing out an error in the previous version of this manuscript. We are grateful for our fruitful conversations with Michael Tremmel, Nir Mandelker, and Vivienne Baldasarre. AR acknowledges funding from the NASA Earth and Space Science Fellowship (NESSF) grant number 80NSSC17K0459. FP acknowledges funding from the NASA Chandra award no. AR8-19021A and from the Nederlandse On-derzoekschool Voor Astronomie (NOVA). NC and FP acknowledge NASA support through Astrophysics Data Analysis Program (ADAP) grant NNX16AF29G.
PY - 2019
Y1 - 2019
N2 - There exist hitherto unexplained fluctuations in the cosmic infrared background on arcminute scales and larger. These have been shown to cross-correlate with the cosmic X-ray background, leading several authors to attribute the excess to a high-redshift growing black hole population. In order to investigate potential sources that could explain this excess, in this paper, we develop a new framework to compute the power spectrum of undetected sources that do not have constant flux as a function of halo mass. In this formulation, we combine a semi-analytic model for black hole growth and their simulated spectra from hydrodynamical simulations. Revisiting the possible contribution of a high-redshift black hole population, we find that too much black hole growth is required at early epochs for z > 6 accretion to explain these fluctuations. Examining a population of accreting black holes at more moderate redshifts, z ∼ 2-3, we find that such models produce a poor fit to the observed fluctuations while simultaneously overproducing the local black hole mass density. Additionally, we rule out the hypothesis of a missing Galactic foreground of warm dust that produces coherent fluctuations in the X-ray via reflection of Galactic X-ray binary emission. Although we firmly rule out accreting massive black holes as the source of these missing fluctuations, additional studies will be required to determine their origin.
AB - There exist hitherto unexplained fluctuations in the cosmic infrared background on arcminute scales and larger. These have been shown to cross-correlate with the cosmic X-ray background, leading several authors to attribute the excess to a high-redshift growing black hole population. In order to investigate potential sources that could explain this excess, in this paper, we develop a new framework to compute the power spectrum of undetected sources that do not have constant flux as a function of halo mass. In this formulation, we combine a semi-analytic model for black hole growth and their simulated spectra from hydrodynamical simulations. Revisiting the possible contribution of a high-redshift black hole population, we find that too much black hole growth is required at early epochs for z > 6 accretion to explain these fluctuations. Examining a population of accreting black holes at more moderate redshifts, z ∼ 2-3, we find that such models produce a poor fit to the observed fluctuations while simultaneously overproducing the local black hole mass density. Additionally, we rule out the hypothesis of a missing Galactic foreground of warm dust that produces coherent fluctuations in the X-ray via reflection of Galactic X-ray binary emission. Although we firmly rule out accreting massive black holes as the source of these missing fluctuations, additional studies will be required to determine their origin.
KW - Black hole physics
KW - Cosmic background radiation
KW - Galaxies: active
KW - Infrared: diffuse background
KW - Quasars: general
KW - X-rays: diffuse background
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U2 - 10.1093/mnras/stz1891
DO - 10.1093/mnras/stz1891
M3 - Article
AN - SCOPUS:85083175558
VL - 489
SP - 1006
EP - 1022
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
SN - 0035-8711
IS - 1
ER -