Cosmological test using the high-redshift detection rate of FSRQs with the Square Kilometer Array
Abstract
We present a phenomenological method for predicting the number of Flat Spectrum Radio Quasars (FSRQs) that should be detected by upcoming Square Kilometer Array (SKA) SKA1-MID Wide Band 1 and Medium-Deep band 2 surveys. We use the Fermi Blazar Sequence and mass estimates of Fermi FSRQs, and gamma-ray emitting Narrow Line Seyfert 1 galaxies, to model the radio emission of FSRQs as a function of mass alone, assuming a near-Eddington accretion rate, which is suggested by current quasar surveys at z > 6. This is used to determine the smallest visible black hole mass as a function of redshift in two competing cosmologies we compare in this paper: the standard LCDM model and the R_h=ct universe. We then apply lockstep growth to the observed black-hole mass function at in order to devolve that population to higher redshifts and determine the number of FSRQs detectable by the SKA surveys as a function of z. We find that at the redshifts for which this method is most valid, LCDM predicts ~30 times more FSRQs than R_h=ct for the Wide survey, and ~100 times more in the Medium-Deep survey. These stark differences will allow the SKA surveys to strongly differentiate between these two models, possibly rejecting one in comparison with the other at a high level of confidence.
Keywords
Cite
@article{arxiv.1905.08086,
title = {Cosmological test using the high-redshift detection rate of FSRQs with the Square Kilometer Array},
author = {Kyle Leaf and Fulvio Melia},
journal= {arXiv preprint arXiv:1905.08086},
year = {2021}
}
Comments
8 pages, 5 figures, 3 tables. Accepted for publication in MNRAS