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Title: Unseen Progenitors of Luminous High- z Quasars in the R {sub h} = ct Universe

Abstract

Quasars at high redshift provide direct information on the mass growth of supermassive black holes (SMBHs) and, in turn, yield important clues about how the universe evolved since the first (Pop III) stars started forming. Yet even basic questions regarding the seeds of these objects and their growth mechanism remain unanswered. The anticipated launch of eROSITA and ATHENA is expected to facilitate observations of high-redshift quasars needed to resolve these issues. In this paper, we compare accretion-based SMBH growth in the concordance ΛCDM model with that in the alternative Friedmann–Robertson–Walker cosmology known as the R {sub h} = ct universe. Previous work has shown that the timeline predicted by the latter can account for the origin and growth of the ≳10{sup 9} M {sub ⊙} highest redshift quasars better than that of the standard model. Here, we significantly advance this comparison by determining the soft X-ray flux that would be observed for Eddington-limited accretion growth as a function of redshift in both cosmologies. Our results indicate that a clear difference emerges between the two in terms of the number of detectable quasars at redshift z ≳ 7, raising the expectation that the next decade will provide the observational data neededmore » to discriminate between these two models based on the number of detected high-redshift quasar progenitors. For example, while the upcoming ATHENA mission is expected to detect ∼0.16 (i.e., essentially zero) quasars at z ∼ 7 in R {sub h} = ct , it should detect ∼160 in ΛCDM—a quantitatively compelling difference.« less

Authors:
 [1];  [2]
  1. Physics Department, Xavier University, Cincinnati, OH 45207 (United States)
  2. Department of Physics, The Applied Math Program, and Department of Astronomy, The University of Arizona, AZ 85721 (United States)
Publication Date:
OSTI Identifier:
22679861
Resource Type:
Journal Article
Journal Name:
Astrophysical Journal
Additional Journal Information:
Journal Volume: 846; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0004-637X
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BLACK HOLES; COMPARATIVE EVALUATIONS; COMPUTERIZED TOMOGRAPHY; COSMOLOGY; GRAVITATION; MASS; QUASARS; RED SHIFT; SOFT X RADIATION; STANDARD MODEL; STARS; SUPERMASSIVE STARS; UNIVERSE

Citation Formats

Fatuzzo, Marco, and Melia, Fulvio, E-mail: fatuzzo@xavier.edu, E-mail: fmelia@email.arizona.edu. Unseen Progenitors of Luminous High- z Quasars in the R {sub h} = ct Universe. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA8627.
Fatuzzo, Marco, & Melia, Fulvio, E-mail: fatuzzo@xavier.edu, E-mail: fmelia@email.arizona.edu. Unseen Progenitors of Luminous High- z Quasars in the R {sub h} = ct Universe. United States. doi:10.3847/1538-4357/AA8627.
Fatuzzo, Marco, and Melia, Fulvio, E-mail: fatuzzo@xavier.edu, E-mail: fmelia@email.arizona.edu. Sun . "Unseen Progenitors of Luminous High- z Quasars in the R {sub h} = ct Universe". United States. doi:10.3847/1538-4357/AA8627.
@article{osti_22679861,
title = {Unseen Progenitors of Luminous High- z Quasars in the R {sub h} = ct Universe},
author = {Fatuzzo, Marco and Melia, Fulvio, E-mail: fatuzzo@xavier.edu, E-mail: fmelia@email.arizona.edu},
abstractNote = {Quasars at high redshift provide direct information on the mass growth of supermassive black holes (SMBHs) and, in turn, yield important clues about how the universe evolved since the first (Pop III) stars started forming. Yet even basic questions regarding the seeds of these objects and their growth mechanism remain unanswered. The anticipated launch of eROSITA and ATHENA is expected to facilitate observations of high-redshift quasars needed to resolve these issues. In this paper, we compare accretion-based SMBH growth in the concordance ΛCDM model with that in the alternative Friedmann–Robertson–Walker cosmology known as the R {sub h} = ct universe. Previous work has shown that the timeline predicted by the latter can account for the origin and growth of the ≳10{sup 9} M {sub ⊙} highest redshift quasars better than that of the standard model. Here, we significantly advance this comparison by determining the soft X-ray flux that would be observed for Eddington-limited accretion growth as a function of redshift in both cosmologies. Our results indicate that a clear difference emerges between the two in terms of the number of detectable quasars at redshift z ≳ 7, raising the expectation that the next decade will provide the observational data needed to discriminate between these two models based on the number of detected high-redshift quasar progenitors. For example, while the upcoming ATHENA mission is expected to detect ∼0.16 (i.e., essentially zero) quasars at z ∼ 7 in R {sub h} = ct , it should detect ∼160 in ΛCDM—a quantitatively compelling difference.},
doi = {10.3847/1538-4357/AA8627},
journal = {Astrophysical Journal},
issn = {0004-637X},
number = 2,
volume = 846,
place = {United States},
year = {2017},
month = {9}
}