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Related papers: A cosmological test with compact radio sources

200 papers

Current and upcoming surveys will measure the cosmological parameters with an extremely high accuracy. The primary goal of these observations is to eliminate some of the currently viable cosmological models created to explain the late time…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Savvas Nesseris , Domenico Sapone

We explore the use of the mass spectrum of neutron stars and black holes in gravitational-wave compact binary sources as a cosmological probe. These standard siren sources provide direct measurements of luminosity distance. In addition,…

Cosmology and Nongalactic Astrophysics · Physics 2022-08-15 Jose María Ezquiaga , Daniel E. Holz

This paper advances a general proposal for testing non-standard cosmological models by means of observational relations of cosmological point sources in some specific waveband, and their use in the context of the data provided by the galaxy…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Marcelo B. Ribeiro

Using the final version of the VLA FIRST survey (Becker et al. 2003), the optical Sloan Digital Sky Survey Data Release 3 (DR3) quasar list and a series of carefully selected criteria, we have defined the largest homogeneous population of…

Astrophysics · Physics 2009-11-11 E. Xanthopoulos , R. H. Becker , W. H. deVries , R. L. White

JWST galaxy deep spectral surveys provide a unique opportunity to trace a broad range of evolutionary features of galaxies and the intergalactic medium given the huge distance the photons are propagating. We have analyzed the spectral data…

Astrophysics of Galaxies · Physics 2025-05-09 N. Galikyan , A. A. Kocharyan , V. G. Gurzadyan

The dipole anisotropy seen in the {cosmic microwave background radiation} is interpreted as due to our peculiar motion. The Cosmological Principle implies that this cosmic dipole signal should also be present, with the same direction, in…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-24 Carlos A. P. Bengaly , Thilo M. Siewert , Dominik J. Schwarz , Roy Maartens

Almost all cosmologists accept nowadays that the redshift of the galaxies is due to the expansion of the Universe (cosmological redshift), plus some Doppler effect of peculiar motions, but can we be sure of this fact by means of some other…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-08 Martin Lopez-Corredoira

In this work we study the magnitude-redshift relation of a non-standard cosmological model. The model under consideration was firstly investigated within a special case of metric-affine gravity (MAG) and was recently recovered via different…

General Relativity and Quantum Cosmology · Physics 2009-04-03 Dirk Puetzfeld , Xuelei Chen

We present a method of calibrating the properties of photometric redshift bins as part of a larger Markov Chain Monte Carlo (MCMC) analysis for the inference of cosmological parameters. The redshift bins are characterised by their mean and…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-02 Michael McLeod , Sreekumar T. Balan , Filipe B. Abdalla

There currently exist many observations which are not consistent with the cosmological principle. We review these observations with a particular emphasis on those relevant for Square Kilometre Array (SKA). In particular, several different…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-03 Shamik Ghosh , Pankaj Jain , Gopal Kashyap , Rahul Kothari , Sharvari Nadkarni-Ghosh , Prabhakar Tiwari

We review observational tests for the homogeneity of the Universe on large scales. Redshift and peculiar velocity surveys, radio sources, the X-Ray Background, the Lyman-alpha forest and the Cosmic Microwave Background are used to set…

Astrophysics · Physics 2016-08-30 Ofer Lahav

We use measurements of the galaxy-cluster angular size versus redshift to test and compare the standard model (LCDM) and the R_h=ct Universe. We show that the latter fits the data with a reduced chi^2_dof=0.786 for a Hubble constant H_0=…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-25 Jun-Jie Wei , Xue-Feng Wu , Fulvio Melia

Published data from long-term observations of a strip of sky at declination +5 degrees carried out at 7.6 cm on the RATAN-600 radio telescope are used to estimate some statistical properties of radio sources. Limits on the sensitivity of…

Cosmology and Nongalactic Astrophysics · Physics 2012-05-24 Yu. N. Parijskij , N. S. Soboleva , A. V. Temirova , N. N. Bursov , O. P. Zhelenkova

Measuring the alignment of polarized radio sources requires comparing vectors at different locations on the sky, i.e. on a sphere. A test of alignment is derived herein. While both large scale and coordinate independent, the test avoids the…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-13 Richard Shurtleff

We have compiled a sample of 234 ultra-steep-spectrum (USS) selected radio sources in order to find high-redshift radio galaxies. The sample covers the declination range -40deg < DEC < -30deg in the overlap region between the 1400-MHz NRAO…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-13 J. J. Bryant , J. W. Broderick , H. M. Johnston , R. W. Hunstead , B. M. Gaensler , C. De Breuck

Context. Explaining the accelerated expansion of the Universe is one of the fundamental challenges in physics today. Cosmography provides information about the evolution of the universe derived from measured distances, assuming only that…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-05 Marek Demianski , Ester Piedipalumbo , Disha Sawant , Lorenzo Amati

Many of the compact extragalactic radio sources that are used as fiducial points to define the celestial reference frame are known to have proper motions detectable with long-term geodetic/astrometric Very Long Baseline Interferometry…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-16 A. Moór , S. Frey , S. B. Lambert , O. Titov , J. Bakos

I review some recent cosmological studies based on redshift surveys of radio sources selected at low frequencies. The accretion rate onto the central black hole is identified as the basis of a crude physical division of the low-frequency…

Astrophysics · Physics 2007-05-23 Steve Rawlings

Cosmography provides a direct method to map the expansion history of the Universe in a model-independent way. Recently, different kinds of observations have been used in cosmographic analyses, such as SNe Ia and gamma ray bursts…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-06 R. F. L. Holanda , J. S. Alcaniz , J. C. Carvalho

We use 118 H$\beta$ quasar (QSO) observations in the redshift range $0.0023 \leq z \leq 0.89$ to simultaneously constrain cosmological model parameters and QSO 2-parameter radius-luminosity ($R-L$) relation parameters in six different…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-16 Narayan Khadka , Mary Loli Martínez-Aldama , Michal Zajaček , Bożena Czerny , Bharat Ratra