Redshift evolution of the X-ray and UV luminosity relation of quasars: calibrated results from SNe Ia

Abstract

Quasars could serve as standard candles if the relation between their ultraviolet and X-ray luminosities can be accurately calibrated. Previously, we developed a model-independent method to calibrate quasar standard candles using the distances-redshift relation reconstructed from Type Ia supernova at z<2 using Gaussian process regression. Interestingly, we found that the calibrated quasar standard candle dataset preferred a deviation from $\Lambda$CDM at redshifts above z>2. One interpretation of these findings is that the calibration parameters of the quasar UV-X-ray luminosity relationship evolves with redshift. In order to test the redshift dependence of the quasar calibration in a model-independent manner, we divided the quasar sample whose redshift overlap with the redshift coverage of Pantheon+ Type Ia supernova compilation into two sub-samples: a low-redshift quasar sub-sample and a high-redshift quasar sub-sample. Our present results show that there is about a 4$\sigma$ inconsistency between the quasar parameters inferred from the high-redshift quasar sub-sample and from the low-redshift sub-sample if no evolution of the quasar relation is considered. This inconsistency suggests the necessity of considering redshift evolution for the relationship between the quasars${}^{\prime }$ ultraviolet and X-ray luminosities. We then test an explicit parametrization of the redshift evolution of the quasar calibration parameters via $\gamma (z)={\gamma }_0+{\gamma }_1(1+z)$ and $\beta (z)={\beta }_0+{\beta }_1(1+z)$. Combining this redshift-dependent calibration relationship with the distance-redshift relationship reconstructed from Pantheon+ supernova compilation, we find the high-redshift sub-sample and low-redshift sub-sample become consistent at the 1$\sigma$ level, which means that the parameterized form of $\gamma (z)$ and $\beta (z)$ works well at describing the evolution of the quasar calibration parameters.

arXiv comment12 pages, 7 figures

References in corpus (32)

• emcee: The MCMC Hammer
• In the Realm of the Hubble tension $-$ a Review of Solutions
• Large Magellanic Cloud Cepheid Standards Provide a 1% Foundation for the Determination of the Hubble Constant and Stronger Evidence for Physics Beyond LambdaCDM
• A luminous quasar at a redshift of z = 7.085
• An 800-million-solar-mass black hole in a significantly neutral Universe at redshift 7.5
• The Pantheon+ Analysis: The Full Dataset and Light-Curve Release
• Everything You Always Wanted To Know About The Cosmological Constant Problem (But Were Afraid To Ask)
• A Luminous Quasar at Redshift 7.642
• The X-ray to optical-UV luminosity ratio of X-ray selected Type 1 AGN in XMM-COSMOS
• Gaussian Process Cosmography
• A Hubble Diagram for Quasars
• Quasars as standard candles III. Validation of a new sample for cosmological studies
• Nonparametric Reconstruction of the Dark Energy Equation of State
• A new cosmological distance measure using AGN
• Quasars as standard candles I: The physical relation between disc and coronal emission
• A model-independent determination of the Hubble constant from lensed quasars and supernovae using Gaussian process regression
• Super-Eddington accreting massive black holes as long-lived cosmological standards
• Nonparametric Reconstruction of the Dark Energy Equation of State from Diverse Data Sets
• Using quasar X-ray and UV flux measurements to constrain cosmological model parameters
• Determining the range of validity of quasar X-ray and UV flux measurements for constraining cosmological model parameters
• Determining Model-independent $H_0$ and Consistency Tests
• How to use GP: Effects of the mean function and hyperparameter selection on Gaussian Process regression
• A new cosmological distance measure using AGN X-ray variability
• Model independent inference of the expansion history and implications for the growth of structure
• Hubble diagram at higher redshifts: Model independent calibration of quasars
• Variability and the X-ray/UV ratio of Active Galactic Nuclei
• On the Scatter in the Radius - Luminosity Relationship for Active Galactic Nuclei
• Quasars as high-redshift standard candles
• The High-z Quasar Hubble Diagram
• Cosmology with AGN: can we use quasars as standard candles?
• Redshift Evolution and Non-Universal Dispersion of Quasar Luminosity Correlation
• Redshift-evolutionary X-ray and UV luminosity relation of quasars from Gaussian copula

Cited by in corpus (3)

• Probing the Cosmic Distance Duality Relation via Non-Parametric Reconstruction for High Redshifts
• Breaking the Mass-sheet Degeneracy in Time-delay Cosmology with Lensed and Unlensed Type Ia Supernovae
• Redshift Evolution of the HII Galaxy $L$-$\sigma$ Relation: Gaussian Process Analysis and Cosmological Implications