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Related papers: Revisiting the NVSS number count dipole

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According to the Cosmological Principle, the matter distribution on very large scales should have a kinematic dipole that is aligned with that of the CMB. We determine the dipole anisotropy in the number counts of two all-sky surveys of…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-11 C. A. P. Bengaly , R. Maartens , M. G. Santos

The dipole moment in the angular distribution of the cosmic microwave background (CMB) is thought to originate from the Doppler effect and our motion relative to the CMB frame. Observations of large-scale structure (LSS) should show a…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-12 Yun-Ting Cheng , Tzu-Ching Chang , Adam Lidz

The source count dipole from wide-area radio continuum surveys allows us to test the cosmological standard model. Many radio sources have multiple components, which can cause an overdispersion of the source counts distribution. We account…

We examine the sky distribution of radio galaxies in the NRAO VLA Sky Survey (NVSS) and the Rapid ASKAP Continuum Survey (RACS). Analyses of these samples have reported tension between their inferred dipoles and the kinematic dipole of the…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-05 Oliver T. Oayda , Vasudev Mittal , Geraint F. Lewis , Tara Murphy

We study the angular clustering of $\sim 6\times 10^5$ NVSS sources on scales $\gtrsim 50 h^{-1}$ Mpc in the context of the $\Lambda$CDM scenario. The analysis partially relies on the redshift distribution of 131 radio galaxies, inferred…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-13 Adi Nusser , Prabhakar Tiwari

We describe the procedure of the construction of a sample of distant ($z>0.3$) radio galaxies using the NED, CATS and SDSS databases for further use in various statistical tests. We believe the sample to be free of objects with quasar…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 M. L. Khabibullina , O. V. Verkhodanov

We use linear estimators to determine the magnitude and direction of the cosmic radio dipole from the NRAO VLA Sky Survey (NVSS) and the Westerbork Northern Sky Survey (WENSS). We show that special attention has to be given to the issues of…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-25 Matthias Rubart , Dominik J. Schwarz

In the present paper we study the radio sources in the NRAO VLA SKY Survey (NVSS) analysing its power spectrum and galaxy distribution. There is a discrepancy between the theoretical models in the literature and the data at large scales. A…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-03 A. Marcos-Caballero , P. Vielva , E. Martinez-Gonzalez , F. Finelli , A. Gruppuso , F. Schiavon

We measure the angular power spectrum of radio galaxies in the NRAO VLA Sky Survey (NVSS) using two independent methods: direct spherical harmonic analysis and maximum likelihood estimation. The results are consistent and can be understood…

Astrophysics · Physics 2009-11-10 Chris Blake , Pedro G. Ferreira , Julian Borrill

We perform observational tests of statistical isotropy using data from large-scale structure surveys spanning a wide range of wavelengths. Using data from 2MASS, 2MRS, and NVSS galaxies, and BATSE gamma-ray bursts, we constrain the…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-10 Cameron Gibelyou , Dragan Huterer

We use numerical simulations to investigate the behaviour of the dipole moment of the spatial distribution of different kinds of mass tracers. We select density peaks of the simulated matter distribution with mean separations of 38 and 30…

Astrophysics · Physics 2015-06-24 V. Kolokotronis , M. Plionis , P. Coles , S. Borgani , L. Moscardini

We present new results on the clustering and three-dimensional distribution of radio galaxies from the Texas-Oxford NVSS Structure (TONS) survey. The TONS survey was constructed to look at the distribution of radio galaxies in a region of…

Astrophysics · Physics 2017-08-23 Kate Brand , Steve Rawlings , Joe Tufts , Gary Hill

The Cosmic Radio Dipole is of fundamental interest to cosmology. Recent studies revealed open questions about the nature of the observed Cosmic Radio Dipole. We use simulated source count maps to test a linear and a quadratic estimator for…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-07 Thilo M. Siewert , Matthias Schmidt-Rubart , Dominik J. Schwarz

We study the dipole anisotropy in integrated linearly polarization flux density in NRAO VLA Sky Survey (NVSS). We extract the anisotropy parameters in the number counts, number counts weighted by polarization observables, i.e. degree of…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-27 Prabhakar Tiwari , Pankaj Jain

We study the dipole anisotropy in number counts and flux density weighted number counts {or sky brightness} in the NRAO VLA Sky Survey (NVSS) data. The dipole anisotropy is expected due to our local motion with respect to the CMBR rest…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-29 Prabhakar Tiwari , Rahul Kothari , Abhishek Naskar , Sharvari Nadkarni-Ghosh , Pankaj Jain

Our motion through the Universe generates a dipole in the temperature anisotropies of the Cosmic Microwave Background (CMB) and also in the angular distribution of sources. If the cosmological principle is valid, these two dipoles are…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-09 Charles Dalang , Camille Bonvin

We measure the angular two-point correlation and angular power spectrum from the NRAO VLA Sky Survey (NVSS) of radio galaxies. They are found to be consistent with the best-fit cosmological model from the Planck analysis, and with the…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-29 Song Chen , Dominik J. Schwarz

(Abridged Abstract) We calculate the expected amplitude of the dipole and higher spherical harmonics in the angular distribution of radio galaxies. The median redshift of radio sources in existing catalogues is z=1, which allows us to study…

Astrophysics · Physics 2009-10-16 Audra Baleisis , Ofer Lahav , Andrew J. Loan , Jasper V. Wall

There have been recent reports of unexpectedly large velocity dipole in the NRAO VLA Sky Survey data. We investigate whether the excess in the NVSS dipole reported can be of cosmological origin. We assume a long wavelength inhomogeneous…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-26 Shamik Ghosh

We study the possibility of using correlations between spatial modulations in the observed luminosity distribution of galaxies and the underlying density field as a cosmological probe. Considering redshift ranges, where magnification…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-07 Martin Feix
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