Bharat Ratra

activity

20232026

most citedUsing non-DESI data to confirm and strengthen the DESI 2024 spatially-flat

w_{0} w_{a}

CDM cosmological parameterization result

107 citations · 206 across the 13 of their papers we have counts for

collaborators

13 papers

astro-ph.CO2026

Is the $w_{0} w_{a}$ CDM cosmological parameterization evidence for dark energy dynamics partially caused by the excess smoothing of Planck PR4 CMB anisotropy data?

Javier de Cruz Pérez, Chan-Gyung Park, Bharat Ratra

We study the performance of the flat $Λ$ CDM model and the dynamical dark energy parameterizations $w_{0}$ CDM and $w_{0} w_{a}$ CDM, in which the dark energy (DE) equation of state is eithe…

astro-ph.GA2025

Standardizing reverberation-mapped H $β$ active galactic nuclei using time-averaged radius $-$ luminosity relations with 5100\,Å\,, broad H $β$ , and narrow \OIII\ luminosities

Shulei Cao, Amit Kumar Mandal, Michal Zajaček +1

Active galactic nuclei (AGN) have been studied as alternate probes in cosmology due to their large and stable luminosities and broad redshift range. Previously it was shown that hi…

astro-ph.CO2025★ 4 cited

Updated observational constraints on $ϕ$ CDM dynamical dark energy cosmological models

Chan-Gyung Park, Bharat Ratra

We present updated observational constraints on the spatially flat $ϕ$ CDM model, where dark energy is described by a minimally coupled scalar field $ϕ$ with an inverse power-law po…

astro-ph.GA2025

Standardizing a larger, higher-quality, homogeneous sample of reverberation-mapped H $β$ active galactic nuclei using the broad-line region radius-luminosity relation

Shulei Cao, Amit Kumar Mandal, Michal Zajaček +1

We present a high-quality, homogeneous sample of 157 H $β$ reverberation-mapped active galactic nuclei (RM AGNs) spanning redshifts $0.00308 \leq z \leq 0.8429$ , which is approximat…

astro-ph.CO2025★ 4 cited

Testing the consistency of new Amati-correlated gamma-ray burst dataset cosmological constraints with those from better-established cosmological data

Shulei Cao, Bharat Ratra

Gamma-ray bursts (GRBs) are promising cosmological probes for exploring the Universe at intermediate redshifts ( $z$ ). We analyze 151 Fermi-observed long GRBs (datasets A123 and A28…

astro-ph.CO2025★ 8 cited

Is excess smoothing of Planck CMB ansiotropy data partially responsible for evidence for dark energy dynamics in other $w (z)$ CDM parametrizations?

Chan-Gyung Park, Bharat Ratra

We study spatially-flat dynamical dark energy parametrizations, $w (z)$ CDM, with redshift-dependent dark energy equation of state parameter $w (z)$ expressed using three different qu…

astro-ph.GA2024

Standardizing reverberation-mapped H $α$ and H $β$ active galactic nuclei using radius--luminosity relations involving monochromatic and broad H $α$ luminosities

Shulei Cao, Amit Kumar Mandal, Michal Zajaček +2

We test the standardizability of a homogeneous sample of 41 lower-redshift ( $0.00415 \leq z \leq 0.474$ ) active galactic nuclei (AGNs) reverberation-mapped (RM) using the broad H $α$ …

astro-ph.CO2024★ 33 cited

Is the $w_{0} w_{a}$ CDM cosmological parameterization evidence for dark energy dynamics partially caused by the excess smoothing of Planck CMB anisotropy data?

Chan-Gyung Park, Javier de Cruz Perez, Bharat Ratra

We study the performance of the spatially-flat dynamical dark energy (DE) $w_{0} w_{a}$ CDM parameterization, with redshift-dependent DE fluid equation of state parameter $w(z) = w_0 + w…

astro-ph.CO2024★ 107 cited

Using non-DESI data to confirm and strengthen the DESI 2024 spatially-flat $w_{0} w_{a}$ CDM cosmological parameterization result

Chan-Gyung Park, Javier de Cruz Perez, Bharat Ratra

We use a combination of Planck cosmic microwave background (CMB) anisotropy data and non-CMB data that include Pantheon+ type Ia supernovae (SNIa), Hubble parameter [ $H (z)$ ], growt…

astro-ph.CO2024★ 1 cited

Updated observational constraints on spatially-flat and non-flat $Λ$ CDM and XCDM cosmological models

Javier de Cruz Perez, Chan-Gyung Park, Bharat Ratra

We study 6 LCDM models, with 4 allowing for non-flat geometry and 3 allowing for a non-unity lensing consistency parameter $A_{L}$ . We also study 6 XCDM models with a dynamical dark…

astro-ph.CO2024★ 12 cited

Testing the standardizability of, and deriving cosmological constraints from, a new Amati-correlated gamma-ray burst data compilation

Shulei Cao, Bharat Ratra

By using gamma-ray burst (GRB) data to simultaneously constrain Amati correlation parameters and cosmological parameters in six spatially-flat and nonflat dark energy cosmological…

astro-ph.CO2024★ 29 cited

Effects of type Ia supernovae absolute magnitude priors on the Hubble constant value

Yun Chen, Suresh Kumar, Bharat Ratra +1

We systematically explore the influence of the prior of the peak absolute magnitude ( $M$ ) of type Ia supernovae (SNe Ia) on the measurement of the Hubble constant ( $H_{0}$ ) from SNe…

astro-ph.CO2023★ 8 cited

Low- and high-redshift H II starburst galaxies obey different luminosity-velocity dispersion relations

Shulei Cao, Bharat Ratra

To determine whether or not H II starburst galaxies (H IIG) are standardizable candles, we study the correlation between the H $β$ luminosity ( $L$ ) and the velocity dispersion ( $σ$ )…

Is the w0​wa​CDM cosmological parameterization evidence for dark energy dynamics partially caused by the excess smoothing of Planck PR4 CMB anisotropy data?

Standardizing reverberation-mapped Hβ active galactic nuclei using time-averaged radius−luminosity relations with 5100\,Å\,, broad Hβ, and narrow \OIII\ luminosities

Updated observational constraints on ϕCDM dynamical dark energy cosmological models

Standardizing a larger, higher-quality, homogeneous sample of reverberation-mapped Hβ active galactic nuclei using the broad-line region radius-luminosity relation

Testing the consistency of new Amati-correlated gamma-ray burst dataset cosmological constraints with those from better-established cosmological data

Is excess smoothing of Planck CMB ansiotropy data partially responsible for evidence for dark energy dynamics in other w(z)CDM parametrizations?

Standardizing reverberation-mapped Hα and Hβ active galactic nuclei using radius--luminosity relations involving monochromatic and broad Hα luminosities

Is the w0​wa​CDM cosmological parameterization evidence for dark energy dynamics partially caused by the excess smoothing of Planck CMB anisotropy data?

Using non-DESI data to confirm and strengthen the DESI 2024 spatially-flat w0​wa​CDM cosmological parameterization result

Updated observational constraints on spatially-flat and non-flat ΛCDM and XCDM cosmological models

Testing the standardizability of, and deriving cosmological constraints from, a new Amati-correlated gamma-ray burst data compilation

Effects of type Ia supernovae absolute magnitude priors on the Hubble constant value

Low- and high-redshift H II starburst galaxies obey different luminosity-velocity dispersion relations

Is the $w_{0} w_{a}$ CDM cosmological parameterization evidence for dark energy dynamics partially caused by the excess smoothing of Planck PR4 CMB anisotropy data?

Standardizing reverberation-mapped H $β$ active galactic nuclei using time-averaged radius $-$ luminosity relations with 5100\,Å\,, broad H $β$ , and narrow \OIII\ luminosities

Updated observational constraints on $ϕ$ CDM dynamical dark energy cosmological models

Standardizing a larger, higher-quality, homogeneous sample of reverberation-mapped H $β$ active galactic nuclei using the broad-line region radius-luminosity relation

Is excess smoothing of Planck CMB ansiotropy data partially responsible for evidence for dark energy dynamics in other $w (z)$ CDM parametrizations?

Standardizing reverberation-mapped H $α$ and H $β$ active galactic nuclei using radius--luminosity relations involving monochromatic and broad H $α$ luminosities

Is the $w_{0} w_{a}$ CDM cosmological parameterization evidence for dark energy dynamics partially caused by the excess smoothing of Planck CMB anisotropy data?

Using non-DESI data to confirm and strengthen the DESI 2024 spatially-flat $w_{0} w_{a}$ CDM cosmological parameterization result

Updated observational constraints on spatially-flat and non-flat $Λ$ CDM and XCDM cosmological models