Do reverberationmeasured Hβ quasars provide a useful test of cosmology?
Abstract
We use 118 Hβ quasar (QSO) observations in the redshift range 0.0023 ≤ z ≤ 0.89 to simultaneously constrain cosmological model parameters and QSO 2parameter radiusluminosity (RL) relation parameters in six different cosmological models. We find that the RL relation parameters for these QSOs are independent of the assumed cosmology so these QSOs seem to be standardizable through the RL relation (although there is a complication that might render this untrue). Cosmological constraints obtained using these QSOs are weak, more favour currently decelerated cosmological expansion, and typically are in ~2σ tension with those obtained from a joint analysis of baryon acoustic oscillation and Hubble parameter measurements. Extending the RL relation to a 3parameter one to try to correct for the accretion rate effect does not result in a reduction of the cosmological constraints discrepancy nor does it result in the hopedfor significant reduction of the intrinsic scatter of the RL relation.
 Publication:

Monthly Notices of the Royal Astronomical Society
 Pub Date:
 June 2022
 DOI:
 10.1093/mnras/stac914
 arXiv:
 arXiv:2112.00052
 Bibcode:
 2022MNRAS.513.1985K
 Keywords:

 quasars: emission lines;
 cosmological parameters;
 cosmology: observations;
 dark energy;
 Astrophysics  Cosmology and Nongalactic Astrophysics;
 General Relativity and Quantum Cosmology;
 High Energy Physics  Phenomenology;
 High Energy Physics  Theory
 EPrint:
 20 pages, 7 figures, H$\beta$ QSO data are given