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Related papers: Large-Scale Coherent Dipole Anisotropy ?

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We summarise results for the predicted density and peculiar velocity fields from the PSCz survey. We have used a generalisation of the Path Interchange Zeldovich Approximation to determine the velocity field; the most remarkable feature…

We present a determination of the cosmic microwave background dipole amplitude and direction from the COBE Differential Microwave Radiometers (DMR) first year of data. Data from the six DMR channels are consistent with a Doppler-shifted…

Astrophysics · Physics 2009-10-22 A. Kogut , C. Lineweaver , G. F. Smoot , C. L. Bennett , A. Banday

The Universe on scales $10-100~h^{-1}$ Mpc is dominated by a cosmic web of voids, filaments, sheets and knots of galaxy clusters. These structures participate differently in the global expansion of the Universe: from non-expanding clusters…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-21 Krzysztof Bolejko , M. Ahsan Nazer , David L. Wiltshire

We are in motion against the cosmic backdrop. This motion is evidenced by the systematic temperature shift - or dipole anisotropy - observed in the Cosmic Microwave Background radiation (CMB). Because of the Doppler effect, the temperature…

Astrophysics · Physics 2015-06-24 Chris Blake , Jasper Wall

We measure the anisotropy of the redshift-space power spectrum in the 1.2-Jy and QDOT redshift surveys of IRAS-selected galaxies. On large scales, this anisotropy is caused by coherent peculiar motions, and gravitational instability theory…

Astrophysics · Physics 2015-06-24 Shaun Cole , Karl B. Fisher , David H. Weinberg

Under nonuniform convection, the distribution of diffusive particles can exhibit dipole and quadrupole anisotropy induced by the fluid inertial and shear force, respectively. These convection-related anisotropies, unlike the Compton-Getting…

High Energy Astrophysical Phenomena · Physics 2022-10-26 Yiran Zhang , Siming Liu , Dejin Wu

Several anomalies appear to be present in the large-angle cosmic microwave background (CMB) anisotropy maps of WMAP, including the alignment of large-scale multipoles. Models in which isotropy is spontaneously broken (e.g., by a scalar…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-13 Haoxuan Zheng , Emory F. Bunn

Clustering properties of two samples of X-ray selected AGNs are compared with IR/Optical galactic samples. These are the Einstein Observatory Extended Medium Sensitivity Survey: EMSS; and a sample of 654 ROSAT detected radio quasars. The…

Astrophysics · Physics 2019-08-17 E. Ghaffarsedeh , J. Quenby

Recent studies have shown that the anisotropy is of great value to decipher cosmic rays' origin and propagation. We have built an unified scenario to describe the observations of the energy spectra and the large-scale anisotropy and called…

High Energy Astrophysical Phenomena · Physics 2024-02-29 Ai-feng Li , Qiang Yuan , Wei Liu , Yi-qing Guo

To assess the significance and scale dependence of anomalous large scale modes in the CatWISE quasar data, we generate smoothed number density fields on the sphere and study their extreme values -- maximum, minimum, maximum antipodal…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-10 Akhil Antony , Stephen Appleby , William L Matthewson , Arman Shafieloo

We test claims of large-scale anisotropy in the local expansion rate using cluster scaling relations as distance indicators. Using a Bayesian forward model, we jointly fit the X-ray luminosity--temperature (LT) and thermal…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-06 Tariq Yasin , Richard Stiskalek , Harry Desmond , Sebastian von Hausegger , Pedro G. Ferreira

We prepare the full sky radio galaxy map ($|b|>10^{\circ}$) using the north NVSS and south SUMSS galaxy catalogs and study the large scale multipoles anomalies. These galaxies are roughly at redshift $z \sim 0.8$ and therefore tracing the…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-01 Prabhakar Tiwari , Pavan K. Aluri

We investigate the clustering of galaxies in the QDOT redshift survey of IRAS galaxies. We find that the redshift space two-point correlation function is well approximated by a power-law of slope -1.11+\-0.09, with clustering length…

Astrophysics · Physics 2015-06-24 Ben Moore , Carlos Frenk , George Efstathiou , Will Saunders

We used the FourStar near-IR camera on Magellan-Baade to obtain high S/N H-Band imaging of 66 galaxies with radial velocities of 2000 < V < 5000 km/s. Our goal was to use the superior distance measurements of surface-brightness-fluctuations…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-11 Alan Dressler , Andrew Monson

We probe the isotropy of the Universe with the largest all-sky photometric redshift dataset currently available, namely WISE~$\times$~SuperCOSMOS. We search for dipole anisotropy of galaxy number counts in multiple redshift shells within…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-11 C. A. P. Bengaly , C. P. Novaes , H. S. Xavier , M. Bilicki , A. Bernui , J. S. Alcaniz

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

The arrival directions of Galactic cosmic rays exhibit anisotropies up to the level of one per-mille over various angular scales. Recent observations of TeV-PeV cosmic rays show that the dipole anisotropy has a strong energy dependence with…

High Energy Astrophysical Phenomena · Physics 2019-05-22 Markus Ahlers

Redshift space distortions on large scales can be used to measure the linear growth rate parameter $\ff \approx \Omega^{0.6}/b$. I report here measurements of such distortions in the IRAS 2 Jy, 1.2 Jy, and QDOT redshift surveys, finding…

Astrophysics · Physics 2008-02-03 A. J. S. Hamilton

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 theoretically analyze the dipole anisotropy observed in the quasar distribution from the CatWISE2020 catalog. The catalog data shows a peak around $z\approx 1$, suggesting the presence of a large-scale dipole component. We explore the…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-16 Gopal Kashyap , Naveen K. Singh , Pankaj Jain