arXiv subjects

R. F. L. Holanda

Publications and source records attributed to R. F. L. Holanda.

At least 37 records · Page 2Linked to original sources

arXiv2022

Strong lensing systems and galaxy cluster observations as probe to the cosmic distance duality relation

{In this paper, we use large scale structure observations to test the redshift dependence of cosmic distance duality relation (CDDR), $D_{\rm L}(1+z)^{-2}/D_{\rm A}=η(z)$}, with $D_{\rm L}$ and $D_{\rm A}$, being the luminosity and angular diameter distances, respectively. In order to perform the test, the following data set are considered: strong lensing systems and galaxy cluster measurements (gas mass fractions). No specific cosmological model is adopted, only a flat universe is assumed. { By considering two $η(z)$ parametrizations, It is observed that the CDDR remain redshift independent within $1.5σ$ which is in full agreement with other recent tests involving cosmological data}. It is worth to comment that our results are independent of the baryon budget of galaxy clusters.

astro-ph.CO↗

arXiv2022

A test of the standard dark matter density evolution law using galaxy clusters and cosmic chronometers

In this letter, we implement a test of the standard law for the dark matter density evolution. For this purpose, only a flat universe and the validity of the FRW metric are assumed. A deformed dark matter density evolution law is considered, given by $ρ_c(z) \propto (1+z)^{3+ε}$, and constraints on $ε$ are obtained by using galaxy cluster gas mass fractions, and cosmic chronometers measurements. We find that $ε=0$ within 2$σ$ c.l., in full agreement with other recent analyses.

astro-ph.CO↗

arXiv2021

A search for the variation of speed of light using galaxy cluster gas mass fraction measurements

In this paper, we implement a new method to test the invariance of the speed of light ($c$) as a function of redshift, by combining the measurements of galaxy cluster gas mass fraction, $H(z)$ from cosmic chronometers, and Type-Ia supernovae (SNe Ia). In our analyses, we consider both a constant depletion factor (which corresponds to the ratio by which the cluster gas mass fraction is depleted with respect to the universal baryonic mean) and one varying with redshift. We also consider the influence of different $H_0$ estimates on our results. We look for a variation of $c$, given by $c(z)=c_0(1+c_1z)$. We find a degeneracy between our final results on $c$ variation and the assumptions on the gas mass fraction depletion factor. Most of our analyses indicate negligible variation of the speed of light.

astro-ph.CO↗

arXiv2021

Galaxy clusters, cosmic chronometers and the Einstein equivalence principle

The Einstein equivalence principle in the electromagnetic sector can be violated in modifications of gravity theory generated by a multiplicative coupling of a scalar field to the electromagnetic Lagrangian. In such theories, deviations of the standard result for the cosmic distance duality relation, and a variation of the fine structure constant are expected and are unequivocally intertwined. In this paper, we search for these possible cosmological signatures by using galaxy cluster gas mass fraction measurements and cosmic chronometers. No significant departure from general relativity is found regardless of our assumptions about cosmic curvature or a possible depletion factor evolution in cluster measurements.

astro-ph.CO↗

arXiv2021

Gravitational lens time-delay as a probe of a possible time variation of the fine-structure constant

A new method based on large-scale structure observations is proposed to probe a possible time variation of the fine-structure constant ($α$). Our analyses are based on time-delay of Strong Gravitational Lensing and Type Ia Supernovae observations. By considering a class of runaway dilaton models, where the cosmological evolution of the fine-structure constant is given by $\frac{Δα}α \approx -γ\ln{(1+z)}$, we obtain limits on the physical properties parameter of the model ($γ$) at the level $10^{-2}$ ($1σ$). Although our limits are less restrictive than those obtained by quasar spectroscopy, the approach presented here provides new bounds on the possibility of $\frac{Δα}α \neq 0$ at a different range of redshifts.

astro-ph.CO↗

arXiv2021

Probing variation of the fine-structure constant in runaway dilaton models using Strong Gravitational Lensing and Type Ia Supernovae

In order to probe a possible time variation of the fine-structure constant ($α$), we propose a new method based on Strong Gravitational Lensing and Type Ia Supernovae observations. By considering a class of dilaton runaway models, where $\frac{Δα}α= - γ\ln{(1+z)}$, we obtain constraints on $\frac{Δα}α$ at the level $γ\approx 10^{-2}$ ($γ$ captures the physical properties of the model). Since the data set covers the redshift range $0.075 \leq z \leq 2.2649$, the constraints derived here provide independent bounds on a possible time variation of $α$ at low, intermediate and high redshifts.

astro-ph.CO↗

arXiv2021

On the cosmic distance duality relation and the strong gravitational lens power law density profile

Many new strong gravitational lensing (SGL) systems have been discovered in the last two decades with the advent of powerful new space and ground-based telescopes. The effect of the lens mass model (usually the power-law mass model) on cosmological parameters constraints has been performed recently in literature. In this paper, by using SGL systems and Supernovae type Ia observations, we explore if the power-law mass density profile ($ρ\propto r^{-γ}$) is consistent with the cosmic distance duality relation (CDDR), $D_L(1+z)^{-2}/D_A=η(z)=1$, by considering different lens mass intervals. { It has been obtained that the verification of the CDDR validity is significantly dependent on lens mass interval considered: the sub-sample with $σ_{ap} \geq 300$ km/s (where $σ_{ap}$ is the lens apparent stellar velocity dispersion) is in full agreement with the CDDR validity, the sub-sample with intermediate $σ_{ap}$ values ($200 \leq σ_{ap} < 300)$ km/s is marginally consistent with $η=1$ and, finally, the sub-sample with low $σ_{ap}$ values ($σ_{ap} < 200$ km/s) ruled out the CDDR validity with high statistical confidence. Therefore, if one takes the CDDR as guarantee, our results suggest that using a single density profile is not suitable to describe lens with low $σ_{ap}$ values and it is only an approximate description to lenses with intermediate mass interval. }

astro-ph.CO↗

arXiv2021

Probing the dark matter density evolution law with large scale structures

We propose a new method to explore a possible departure from the standard time evolution law for the dark matter density. We looked for a violation of this law by using a deformed evolution law, given by $ρ_c(z) \propto (1+z)^{3+ε}$, and then constrain $ε$. The dataset used for this purpose consists of Strong Gravitational Lensing data obtained from SLOAN Lens ACS, BOSS Emission-line Lens Survey, Strong Legacy Survey SL2S, and SLACS; along with galaxy cluster X-ray gas mass fraction measurements obtained using the Chandra Telescope. Our analyses show that $ε$ is consistent with zero within 1 $σ$ c.l., but the current dataset cannot rule out with high confidence level interacting models of dark matter and dark energy.

astro-ph.CO↗

arXiv2020

On a possible cosmological evolution of galaxy cluster $Y_{\rm X}-Y_{\rm SZE}$ scaling relation

An important result from self-similar models that describe the process of galaxy cluster formation is the simple scaling relation $Y_{\rm SZE}D_{\rm A}^{2}/C_{\rm XSZE}Y_{\rm X}= C$. In this ratio, $Y_{\rm SZE}$ is the integrated Sunyaev-Zel'dovich effect flux of a cluster, its x-ray counterpart is $Y_{\rm X}$, $C_{\rm XSZE}$ and $C$ are constants and $D_{\rm A}$ is the angular diameter distance to the cluster. In this paper, we consider the cosmic distance duality relation validity jointly with type Ia supernovae observations plus $61$ $Y_{\rm SZE}D_{\rm A}^{2}/C_{\rm XSZE}Y_{\rm X}$ measurements as reported by the Planck Collaboration to explore if this relation is constant in the redshift range considered ($z<0.5$). No one specific cosmological model is used. As basic result, although the data sets are compatible with no redshift evolution within 2$σ$ c.l., a Bayesian analysis indicates that other $C(z)$ functions analyzed in this work cannot be discarded. It is worth to stress that the observational determination of an universal $C(z)$ function turns the $Y_{\rm SZE}D_{\rm A}^{2}/C_{\rm XSZE}Y_{\rm X}$ ratio in an useful cosmological tool to determine cosmological parameters.

astro-ph.CO↗

arXiv2020

Bayesian Comparison of the Cosmic Duality Scenarios

The cosmic distance duality relation (CDDR), $D_{\rm L}(1+z)^{-2}/D_{\rm A}=η=1$, with $D_{\rm L}$ and $D_{\rm A}$, being the luminosity and angular diameter distances, respectively, is a crucial premise in cosmological scenarios. Many investigations try to test CDDR through observational approaches, even some of these ones also consider a deformed CDDR, i.e., $η=η(z)$. In this paper, we use type Ia supernovae luminosity distances and galaxy cluster measurements (their angular diameter distances and gas mass fractions) in order to perform a Bayesian model comparison between $ η(z) $ functions. We show that the data here used are unable to pinpoint, with a high degree of Bayesian evidence, which $η(z)$ function best captures the evolution of CDDR.

astro-ph.CO↗

arXiv2020

A low Hubble Constant from galaxy distribution observations

An accurate determination of the Hubble constant remains a puzzle in observational cosmology. The possibility of a new physics has emerged with a significant tension between the current expansion rate of our Universe measured from the cosmic microwave background by the Planck satellite and from local methods. In this paper, new tight estimates on this parameter are obtained by considering two data sets from galaxy distribution observations: galaxy cluster gas mass fractions and baryon acoustic oscillation measurements. Priors from the Big Bang nucleosynthesis (BBN) were also considered. By considering the flat $Λ$CDM and XCDM models, and the non-flat $Λ$CDM model, our main results are: $H_0=65.9^{+1.5}_{-1.5}$ km s$^{-1}$ Mpc$^{-1}$, $H_0=65.9^{+4.4}_{-4.0}$ km s$^{-1}$ Mpc$^{-1}$ and $H_0=64.3^{+ 4.5}_{- 4.4}$ km s$^{-1}$ Mpc$^{-1}$ in $2σ$ c.l., respectively. These estimates are in full agreement with the Planck satellite results. Our analyses in these cosmological scenarios also support a negative value for the deceleration parameter at least in 3$σ$ c.l..

astro-ph.CO↗

arXiv2019

Acceleration in Friedmann cosmology with torsion

A Friedmann like cosmological model in Einstein-Cartan framework is studied when the torsion function is assumed to be proportional to a single $ϕ(t)$ function coming just from the spin vector contribution of ordinary matter. By analysing four different types of torsion function written in terms of one, two and three free parameters, we found that a model with $ϕ(t)=- αH(t) \big({ρ_{m}(t)}/{ρ_{0c}}\big)^n$ is totally compatible with recent cosmological data, where $α$ and $n$ are free parameters to be constrained from observations, $ρ_m$ is the matter energy density and $ρ_{0c}$ the critical density. The recent accelerated phase of expansion of the universe is correctly reproduced by the contribution coming from torsion function, with a deceleration parameter indicating a transition redshift of about $0.65$.

gr-qc↗

arXiv2019

An estimate of the dark matter density from galaxy clusters and supernovae data

In this paper, we discuss a model-independent way to obtain the present dark matter density parameter ($Ω_{\rm{c,0}}$) by combining gas mass fraction measurements in galaxy clusters ($f_{gas}$), type Ia supernovae (SNe Ia) observations and measurements of the cosmic baryon abundance from observations of absorption systems at high redshifts. Our estimate is $Ω_{\rm{c,0}} = 0.244 \pm 0.013$ ($1σ$). By considering the latest local measurement of the Hubble constant, we obtain $Ω_{\rm{M,0}} = 0.285 \pm 0.013$ ($1σ$) for the total matter density parameter. We also investigate departures of the evolution of the dark matter density with respect to the usual $a^{-3}$ scaling, as usual in interacting models of dark matter and dark energy. As the current data cannot confirm or rule out such an interaction, we perform a forecast analysis to estimate the necessary improvements in number and accuracy of upcoming $f_{gas}$ and SNe Ia observations to detect a possible non-minimal coupling in the cosmological dark sector.

astro-ph.CO↗

arXiv2019

Galaxy cluster Sunyaev-Zel'dovich effect scaling-relation and type Ia supernova observations as a test for the cosmic distance duality relation

In this paper, we propose a new test to the cosmic distance duality relation (CDDR), $D_L=D_A(1+z)^2$, where $D_L$ and $D_A$ are the luminosity and angular diameter distances, respectively. The data used correspond to 61 Type Ia Supernova luminosity distances and $Y_{SZE}-Y_X$ measurements of 61 galaxy clusters obtained by the {\it Planck} mission and the deep XMM-Newton X-ray data, where $Y_{SZE}$ is the integrated comptonization parameter obtained via Sunyaev-Zel'dovich effect observations and $Y_X$ is the X-ray counterpart. More precisely, we use the $Y_{SZE}D_{A}^{2}/C_{XSZE}Y_X$ scaling-relation and a deformed CDDR, such as $D_L/D_A(1+z)^2=η(z)$, to verify if $η(z)$ is compatible with the unity. Two $η(z)$ functions are used, namely, $η(z)=1+η_0 z$ and $η(z)=1+η_0 z /(1+z)$. { We obtain that the CDDR validity ($η_0=0$) is verified within $\approx 1.5σ$ c.l. for both $η(z)$ functions.}.

astro-ph.CO↗

arXiv2019

Galaxy clusters and a possible variation of the fine structure constant

Galaxy clusters have been used as a cosmic laboratory to verify a possible time variation of fundamental constants. Particularly, it has been shown that the ratio $Y_{SZ}D_{A}^{2}/C_{XZS}Y_X $, which is expected to be constant with redshift, can be used to probe a variation of the fine structure constant, $α$. In this ratio, $Y_{SZ}D_{A}^{2}$ is the integrated comptonization parameter of a galaxy cluster obtained via Sunyaev-Zel'dovich (SZ) effect observations multiplied by its angular diameter distance, $D_A$, $Y_X$ is the X-ray counterpart and $C_{XSZ}$ is an arbitrary constant. Using a combination of SZ and X-ray data, a recent analysis found $Y_{SZ}D_{A}^{2}/C_{XZS}Y_X = {\rm{C}} α(z)^{3.5}$, where ${\rm{C}}$ is a constant. In this paper, following previous results that suggest that a variation of $α$ necessarily leads to a violation of the cosmic distance duality relation, $D_L/D_A(1+z)^2 = 1$, where $D_L$ is the luminosity distance of a given source, we derive a new expression, $Y_{SZ}D_{A}^{2}/C_{XSZ}Y_X = {\rm{C}} α^{3.5} η^{-1}(z)$, where $η(z) = D_L/D_A(1+z)^2$. In particular, considering the direct relation $η(z) \propto α(z)^{1/2}$, derived from a class of dilaton runaway models, %class of modified gravity theories, and 61 measurements of the ratio $Y_{SZ}D_{A}^{2}/C_{XSZ}Y_X$ provided by the Planck collaboration, we discuss bounds on a possible variation of $α$. We also estimate the value of the constant $ {\rm{C}}$, which is compatible with the unity at $2σ$ level, indicating that the assumption of isothermality for the temperature profile of the galaxy clusters used in the analysis holds.

astro-ph.CO↗

arXiv2019

Constraints on the cosmic distance duality relation with simulated data of gravitational waves from the Einstein Telescope

The cosmic distance duality relation (CDDR) has been test through several astronomical observations in the last years. This relation establishes a simple equation relating the angular diameter ($D_A$) and luminosity ($D_L$) distances at a redshift $z$, $D_LD_A^{-1}(1+z)^{-2}=η=1$. However, only very recently this relation has been observationally tested at high redshifts ($z \approx 3.6$) by using luminosity distances from type Ia supernovae (SNe Ia) and gamma ray bursts (GRBs) plus angular diameter distances from strong gravitational lensing (SGL) observations. The results show that no significant deviation from the CDDR validity has been verified. In this work, we test the potentialities of future luminosity distances from gravitational waves (GWs) sources to impose limit on possible departures of CDDR jointly with current SGL observations. The basic advantage of $D_L$ from GWs is being insensitive to non-conservation of the number of photons. By simulating 600, 900 and 1200 data of GWs using the Einstein Telescope (ET) as reference, we derive limits on $η(z)$ function and obtain that the results will be at least competitive with current limits from the SNe Ia $+$ GRBs $+$ SGLs analyses.

astro-ph.CO↗

arXiv2018

Model independent constraints on transition redshift

This paper aims to put constraints on the transition redshift $z_t$, which determines the onset of cosmic acceleration, in cosmological-model independent frameworks. In order to perform our analyses, we consider a flat universe and {assume} a parametrization for the comoving distance $D_C(z)$ up to third degree on $z$, a second degree parametrization for the Hubble parameter $H(z)$ and a linear parametrization for the deceleration parameter $q(z)$. For each case, we show that {type Ia supernovae} and $H(z)$ data complement each other on the parameter {space} and tighter constrains for the transition redshift are obtained. By {combining} the type Ia supernovae observations and Hubble parameter measurements it is possible to constrain the values of $z_t$, for each approach, as $0.806\pm 0.094$, $0.870\pm 0.063$ and $0.973\pm 0.058$ at 1$σ$ c.l., respectively. Then, such approaches provide cosmological-model independent estimates for this parameter.

astro-ph.CO↗

arXiv2018

X-ray surface brightness observations of galaxy clusters, cosmic opacity and the limits on the matter density parameter

In this work, we use two gas mass fraction samples of galaxy clusters obtained from their X-ray surface brightness observations jointly with recent $H(z)$ data in a flat $Λ$CDM framework to impose limits on cosmic opacity. It is assumed that the galaxy clusters are in hydrostatic equilibrium and their gas mass fraction measurement is constant with redshift. We show that the current limits on the matter density parameter obtained from X-ray gas mass fraction test are strongly dependent on the cosmic transparency assumption even for a flat scenario. Our results are consistent with a transparent universe within $1σ$ c.l. in full agreement with other analyses which used type Ia supernovae, gamma ray burst and $H(z)$ data.

astro-ph.CO↗