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We constructed and presented in the first paper of this series a new sample of 84 large angular size radio galaxies by selecting from the NRAO VLA Sky Survey objects with angular size > 4', declination above +60 degrees and total flux…

Astrophysics · Physics 2009-11-07 L. Lara , I. Marquez , W. D. Cotton , L. Feretti , G. Giovannini , J. M. Marcaide , T. Venturi

One of the possible extensions of Einstein's General Theory of Relativity consists in allowing for the presence of spacetime torsion. The form of the underlying torsion tensor can be chosen such that the homogeneity and isotropy of…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-20 C. M. J. Marques , C. J. A. P. Martins

Measurements of the growth index $\gamma(z)$ provide a clue as to whether Einstein's field equations encompass gravity also on large cosmic scales, those where the expansion of the universe accelerates. We show that the information encoded…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Heinrich Steigerwald , Julien Bel , Christian Marinoni

Considering a well-motivated $f(R)$ modified-gravity model, in which an exponential function of the curvature is included, in this paper we implement a statistical data analysis to set constraints on the parameters of the model, taking into…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-01 Mario A. Acero , A. Oliveros

We compile a complete collection of reliable Hubble parameter $H(z)$ data to redshift $z \leq 2.36$ and use them with the Gaussian Process method to determine continuous $H(z)$ functions for various data subsets. From these continuous…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-04 Hai Yu , Bharat Ratra , Fa-Yin Wang

We use FRIIb radio galaxy redshift-angular size data to constrain cosmological parameters in a dark energy scalar field model. The derived constraints are consistent with but weaker than those determined using Type Ia supernova…

Astrophysics · Physics 2009-11-07 Silviu Podariu , Ruth A. Daly , Matthew P. Mory , Bharat Ratra

Using a new radio sample, 6C* designed to find radio galaxies at z > 4 along with the complete 3CRR and 6CE sample we extend the radio galaxy K-z relation to z~4.5. The 6C* K-z data significantly improve delineation of the K-z relation for…

We present a study of the trends in luminosity, linear size, spectral index, and redshift of classical double radio sources from three complete samples selected at successively fainter low radio-frequency flux-limits. We have been able to…

Astrophysics · Physics 2010-04-06 Katherine M. Blundell , Steve Rawlings , Chris J. Willott

Using a new recently compiled milliarcsecond compact radio data set of 120 intermediate-luminosity quasars in the redshift range $0.46< z <2.76$, whose statistical linear sizes show negligible dependence on redshifts and intrinsic…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-30 Jing-Zhao Qi , Shuo Cao , Marek Biesiada , Xiaogang Zheng , Zong-Hong Zhu

We update gamma-ray burst (GRB) luminosity relations among certain spectral and light-curve features with 139 GRBs. The distance modulus of 82 GRBs at $z>1.4$ can be calibrated with the sample at $z\leq1.4$ by using the cubic spline…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-23 Jun-Jie Wei , Qing-Bo Ma , Xue-Feng Wu

Astrophysical sources such as radio halos and relics in galaxy clusters, supernova remnants and radio galaxies have angular sizes from a few to several $10$s of arcminutes. In radio interferometric imaging of such sources, the largest…

Instrumentation and Methods for Astrophysics · Physics 2017-09-13 Deepak Kumar Deo , Ruta Kale

Deriving the expansion history of the Universe is a major goal of modern cosmology. To date, the most accurate measurements have been obtained with Type Ia Supernovae and Baryon Acoustic Oscillations, providing evidence for the existence of…

We use updated Hubble parameter and baryon acoustic oscillation data, as well as other lower-redshift Type Ia supernova, Mg II reverberation-measured quasar, quasar angular size, H II starburst galaxy, and Amati-correlated gamma-ray burst…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-31 Shulei Cao , Bharat Ratra

In this paper I investigate how well simple power law expansion fits observational data in comparison to the standard $\Lambda$CDM model. I analyze a data set consisting of cosmic chronometer, standard ruler, and standard candle…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-25 Joseph Ryan

Cosmic microwave background measurements have pushed to higher resolution, lower noise, and more sky coverage. These data enable a unique test of the early universe's expansion rate and constituents such as effective number of relativistic…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-05 Alireza Hojjati , Eric V. Linder , Johan Samsing

It is shown that the new observed redshift distributions of various flux-limited samples of radio sources in general are consistent with the predictions of two basic evolutionary models published by Condon (1984) and Dunlop and Peacock…

Astrophysics · Physics 2016-01-27 J. Machalski , M. Jamrozy

In this paper, linear first order expansion of deceleration parameter $q(z)=q_0+q_1(1-a)$ ($M_1$), constant jerk $j=j_0$ ($M_2$) and third order expansion of luminosity distance ($M_3$) are confronted with cosmic observations: SCP 307 SN…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-24 Lixin Xu , Wenbo Li , Jianbo Lu

Recent astronomical observations of SNIa, CMB, as well as BAO in the Sloan Digital Sky Survey, suggest that the current Universe has entered a stage of an accelerated expansion with the transition redshift at $z \simeq 0.5$. While the…

Astrophysics · Physics 2010-11-11 Aleksandra Kurek , Marek Szydlowski

The study of cosmic expansion history and the late time cosmic acceleration from observational data depends on the nuisance parameters associated with the data. For example, the absolute peak magnitude of type Ia supernova associated with…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-19 Bikash R. Dinda

The recent measurements of the power spectrum of Cosmic Microwave Background anisotropies are consistent with the simplest inflationary scenario and big bang nucleosynthesis constraints. However, these results rely on the assumption of a…

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