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We explore a possible time variation of the fine structure constant ($\alpha \equiv e^2/\hbar c$) using the Sunyaev-Zel'dovich effect measurements of galaxy clusters along with their X-ray observations. Specifically, the ratio of the…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-24 Zhi-E Liu , Wen-Fei Liu , Tong-Jie Zhang , Zhong-Xu Zhai , Kamal Bora

We propose a new method to probe a possible time evolution of the fine structure constant $\alpha$ from X-ray and Sunyaev-Zeldovich measurements of the gas mass fraction ($f_{gas}$) in galaxy clusters. Taking into account a direct relation…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-01 R. F. L. Holanda , S. J. Landau , J. S. Alcaniz , I. E. Sanchez G. , V. C. Busti

As is well known, measurements of the Sunyaev-Zeldovich effect can be combined with observations of the X-ray surface brightness of galaxy clusters to estimate the angular diameter distance to these structures. In this paper, we show that…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-01 R. F. L. Holanda , V. C. Busti , L. R. Colaço , J. S. Alcaniz , S. J. Landau

We propose a new method to probe for variations in the fine structure constant alpha using clusters of galaxies, opening up a window on a new redshift range for such constraints. Hot clusters shine in the X-ray mainly due to bremsstrahlung,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Silvia Galli

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…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-01 R. F. L. Holanda , W. J. C. da Silva

In this paper, new bounds on possible variations of the fine structure constant, $\alpha$, for a class of runaway dilaton models are performed. By considering a possible evolution with redshift, $z$, such as…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-01 R. F. L. Holanda , L. R. Colaço , R. S. Gonçalves , J. S. Alcaniz

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…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-01 R. F. L. Holanda , L. R. Colaço , S. H. Pereira , R. Silva

The angular diameter distances toward galaxy clusters can be determined with measurements of the Sunyaev-Zel'dovich effect and X-ray surface brightness combined with the validity of the distance-duality relation, $D_L(z) (1 +…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-17 R. F. L. Holanda , J. A. S. Lima , M. B. Ribeiro

Testing possible variations in fundamental constants of nature is a crucial endeavor in observational cosmology. This paper investigates potential cosmological variations in the fine structure constant ($\alpha$) through a non-parametric…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-30 Marcelo Ferreira , Rodrigo F. L. Holanda , Javier E. Gonzalez , L. R. Colaço , Rafael C. Nunes

We search for a variation of the electromagnetic fine structure constant ($\alpha \equiv e^2/\hbar c$) using a sample of 58 SZ selected clusters in the redshift range ($0.2<z<1.5$) detected by the South Pole Telescope, along with X-ray…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-12 Kamal Bora , Shantanu Desai

The cosmic distance-duality relation (CDDR), $d_L(z) (1 + z)^{2}/d_{A}(z) = \eta$, where $\eta = 1$ and $d_L(z)$ and $d_A(z)$ are, respectively, the luminosity and the angular diameter distances, holds as long as the number of photons is…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-01 R. S. Gonçalves , A. Bernui , R. F. L. Holanda , J. S. Alcaniz

In this paper, we propose an accurate test of the distance-duality (DD) relation, $\eta=D_{L}(z)(1+z)^{-2}/D_{A}(z)=1$ (where $D_{L}$ and $D_{A}$ are the luminosity distances and angular diameter distances, respectively), with a combination…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Shuo Cao , Nan Liang

{In this paper, we use large scale structure observations to test the redshift dependence of cosmic distance duality relation (CDDR), $D_{\rm L}(1+z)^{-2}/D_{\rm A}=\eta(z)$}, with $D_{\rm L}$ and $D_{\rm A}$, being the luminosity and…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-23 R. F. L. Holanda , F. S. Lima , Akshay Rana , Deepak Jain

Observations in the cosmological domain are heavily dependent on the validity of the cosmic distance-duality (DD) relation, D_L(z) (1 + z)^{2}/D_{A}(z) = 1, an exact result required by the Etherington reciprocity theorem where D_L(z) and…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-13 R. F. L. Holanda , J. A. S. Lima , M. B. Ribeiro

We propose an improved methodology to constrain spatial variations of the fine structure constant using clusters of galaxies. We use the {\it Planck} 2013 data to measure the thermal Sunyaev-Zeldovich effect at the location of 618 X-ray…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-02 I. de Martino , C. J. A. P. Martins , H. Ebeling , D. Kocevski

In recent years, significant progress has been made in building new galaxy clusters samples, at low and high redshifts, from wide-area surveys, particularly exploiting the Sunyaev--Zel'dovich (SZ) effect. A large effort is underway to…

Future high-resolution microwave background measurements hold the promise of detecting galaxy clusters throughout our Hubble volume through their Sunyaev-Zel'dovich (SZ) signature, down to a given limiting flux. The number density of galaxy…

Astrophysics · Physics 2007-05-23 Matthew R. Francis , Rachel Bean , Arthur Kosowsky

In this letter we propose a new and model-independent cosmological test for the distance-duality (DD) relation, \eta=D_{L}(z)(1+z)^{-2}/D_{A}(z)=1, where D_{L} and D_{A} are, respectively, the luminosity and angular diameter distances. For…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-01 R. F. L. Holanda , J. A. S. Lima , M. B. Ribeiro

We have constrained the spatial variation of the fine structure constant using multi-frequency measurements of the thermal Sunyaev-Zeldovich effect of 618 X-ray selected clusters. Although our results are not competitive with the ones from…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-22 I. de Martino , C. J. A. P. Martins , H. Ebeling , D. Kocevski

The possibility of variation of the fundamental constants of nature has been a long-standing question, with important consequences for fundamental physics and cosmology. In particular, it has been shown that variations in the fine-structure…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-01 Rodrigo S. Gonçalves , Susana Landau , Jailson S. Alcaniz , Rodrigo F. L. Holanda
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