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We explore the large to moderate scale anisotropy in distant radio sources using the TGSS ADR1 catalog. We use different measures, i.e. number counts, sky brightness and flux per source, for this study. In agreement with earlier results, we…

Cosmology and Nongalactic Astrophysics · Physics 2019-12-20 Prabhakar Tiwari , Shamik Ghosh , Pankaj Jain

In parallel with advances in microscale imaging techniques, the fields of biology and materials science have focused on precisely extracting particle properties based on their diffusion behavior. Although the majority of real-world…

Mesoscale and Nanoscale Physics · Physics 2024-05-22 Kaito Takanami , Daisuke Taniguchi , Sawako Enoki , Masafumi Kuroda , Yasushi Okada , Yoshiyuki Kabashima

We search for the presence of cosmological neutrino background (CNB) anisotropies in recent WMAP 5-year data using their signature imprinted on modifications to cosmic microwave background (CMB) anisotropy power spectrum. By parametrizing…

We present the first targeted measurement of the power spectrum of anisotropies of the radio synchrotron background, at 140 MHz where it is the overwhelmingly dominant photon background. This measurement is important for understanding the…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-06 A. R. Offringa , J. Singal , S. Heston , S. Horiuchi , D. M. Lucero

We measure the velocity anisotropy profile $\beta(r)$ of different galaxy cluster member populations by analysing the stacked projected phase space of nine massive ($M_\mathrm{200c}>7\times10^{14}$ M$_\odot$) galaxy clusters at intermediate…

Astrophysics of Galaxies · Physics 2026-04-15 E. Maraboli , A. Biviano , C. Grillo , A. Mercurio , L. Pizzuti , P. Rosati , M. D'Addona

Anisotropy in the arrival directions of cosmic rays with energies above 10$^{17}$eV is studied using data from the Akeno 20 km$^2$ array and the Akeno Giant Air Shower Array (AGASA), using a total of about 117,000 showers observed during 11…

The distribution of arrival directions of ultra-high energy cosmic rays may yield clues to their mysterious origin. We introduce a method of {\it invariant statistics} to analyze cosmic ray data which eliminates coordinate-dependent…

Astrophysics · Physics 2009-11-07 Soebur Razzaque , John P. Ralston

We present the line-of-sight (LOS) velocities for 13 distant main sequence Milky Way halo stars with published proper motions. The proper motions were measured using long baseline (5-7 years) multi-epoch HST/ACS photometry, and the LOS…

The signal of dipole anisotropy in quasar number counts is studied using the CatWISE2020 catalog in various color bins. It is found that the dipole signal differs significantly in two color bins, namely, $1.1>W1-W2\ge 0.8$ and…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-28 Mohit Panwar , Pankaj Jain , Amitesh Omar

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

Based on general relativity, it can be argued that deviations from a uniform Hubble flow should be thought of as variations in the Universe's expansion velocity field, rather than being thought of as peculiar velocities with respect to a…

Astrophysics · Physics 2008-11-26 M. L. McClure , C. C. Dyer

The natural outcome of theoretical calculations of microwave background anisotropy is the angular power spectrum ${\cal C}_\ell$ as a function of multipole number $\ell$. Experimental ${\cal C}_\ell$'s are needed for direct comparison.…

Astrophysics · Physics 2009-09-25 J. Richard Bond

We consider the benefits of measuring cosmic statistical anisotropy from redshift-space correlators of the galaxy number density fluctuation and the peculiar velocity field without adopting the plane-parallel (PP) approximation. Since the…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-17 Maresuke Shiraishi , Teppei Okumura , Kazuyuki Akitsu

Angular anisotropy techniques for cosmic diffuse radiation maps are powerful probes, even for quite small data sets. A popular observable is the angular power spectrum; we present a detailed study applicable to any unbinned source skymap…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Sheldon S. Campbell

In his 2021 lecture to the Canadian Association of Physicists Congress, P.J.E. Peebles pointed out that the brightest extra-galactic radio sources tend to be aligned with the plane of the de Vaucouleur Local Supercluster up to redshifts of…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-02 Matthieu Schaller

We showed that the part of strings could be detected by optical method is only 20% from the total available amount of such objects, therefore the gravitational lensing method has to be "completed" by CMB one. We found the general structure…

Astrophysics · Physics 2009-11-13 O. S. Sazhina , M. V. Sazhin , V. N. Sementsov , M. Capaccioli , G. Longo , G. Riccio , G. D'Angelo

The Cosmological Principle states that the Universe is statistically isotropic and homogeneous on large scales. In particular, this implies statistical isotropy in the galaxy distribution, after removal of a dipole anisotropy due to the…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-16 Carlos A. P. Bengaly , Roy Maartens , Nandrianina Randriamiarinarivo , Albert Baloyi

Recent astronomical observations show that the universe may be anisotropic on large scales. The Union2 SnIa data hint that the universe has a preferred direction. If such a cosmological privileged axis indeed exists, one has to consider an…

General Relativity and Quantum Cosmology · Physics 2019-07-03 Amin Salehi , S. Aftabi

We use weighted mean and median statistics techniques to combine individual cosmic microwave background (CMB) anisotropy detections and determine binned, multipole-space, CMB anisotropy power spectra. The resultant power spectra are peaked.…

The role of nearby galactic sources, the supernova remnants, in formation of observed energy spectrum and anisotropy of high-energy cosmic rays is studied. The list of these sources is made up based on radio, X-ray and gamma-ray catalogues.…

High Energy Astrophysical Phenomena · Physics 2013-12-20 L. G. Sveshnikova , O. N. Strelnikova , V. S. Ptuskin
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