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The cosmic radio dipole is an anisotropy in the number counts of radio sources, analogous to the dipole seen in the cosmic microwave background (CMB). Measurements of source counts of large radio surveys have shown that though the radio…

宇宙学与河外天体物理 · 物理学 2023-07-05 J. D. Wagenveld , H-R. Klöckner , D. J. Schwarz

In this review we present a comprehensive discussion of peculiar velocity field measured recently on very large scales with a novel method using X-ray galaxy clusters as tracers. The measurement is based on the kinematic component of the…

宇宙学与河外天体物理 · 物理学 2012-02-06 A. Kashlinsky , F. Atrio-Barandela , H. Ebeling

We show that clusters of galaxies induce step-like wiggles on top of the cosmic microwave background (CMB). The direction of the wiggle is parallel to the large scale gradient of CMB allowing one to isolate the effect from other small scale…

天体物理学 · 物理学 2009-10-31 Uros Seljak , Matias Zaldarriaga

Comparison of peculiar velocities of galaxies with their gravitational accelerations (induced by the density field) is one of the methods to constrain the redshift distortion parameter \beta=(\Omega_m^0.55)/b, where \Omega_m is the…

宇宙学与河外天体物理 · 物理学 2015-02-17 Maciej Bilicki , Michał Chodorowski , Wojciech Hellwing , Thomas Jarrett , Gary Mamon

In this work we consider the changes of the SZ cluster brightness, flux and number counts induced by the motion of the Solar System with respect to the frame defined by the cosmic microwave background (CMB). These changes are connected with…

天体物理学 · 物理学 2009-11-10 J. Chluba , G. Huetsi , R. A. Sunyaev

The shape of the curves defined by the counts of radio sources per unit area as a function of their flux density was one of the earliest cosmological probes. Radio source counts continue to be an area of interest, used to study the relative…

宇宙学与河外天体物理 · 物理学 2015-06-15 Ian Heywood , Matt J. Jarvis , James J. Condon

In order to best improve constraints on cosmological parameters and on models of modified gravity using current and future galaxy surveys it is necessary maximally exploit the available data. As redshift-space distortions mean statistical…

宇宙学与河外天体物理 · 物理学 2017-12-27 Donough Regan

We test the statistical isotropy of the universe by analyzing the distribution of WISE extragalactic sources that were also observed by 2MASS. We pay particular attention to color cuts and foreground marginalization in order to cull a…

宇宙学与河外天体物理 · 物理学 2014-12-04 Mijin Yoon , Dragan Huterer , Cameron Gibelyou , András Kovács , István Szapudi

The exquisitely measured maps of fluctuations in the Cosmic Microwave Background (CMB) present the possibility to test the principle of Statistical Isotropy (SI) of the Universe through systematic observable measures for non-Statistical…

宇宙学与河外天体物理 · 物理学 2023-01-12 Dipanshu , Tarun Souradeep , Shriya Hirve

Cosmological parameters can be measured by comparing peculiar velocities with those predicted from a galaxy density field. Previous work has tested the accuracy of this approach with N-body simulations, but generally on idealised mock…

宇宙学与河外天体物理 · 物理学 2024-03-27 Amber M. Hollinger , Michael J. Hudson

We simulate Planck observations by adopting a detailed model of the microwave sky including monopole, dipole, anisotropies of the cosmic microwave background (CMB) and galactic and extragalactic foregrounds. We estimate the impact of main…

天体物理学 · 物理学 2007-05-23 C. Burigana , D. Maino , N. Mandolesi , F. Villa , L. Valenziano , M. Bersanelli , L. Danese , L. Toffolatti , F. Argüeso

Recently the second phase of Background Imaging of Cosmic Extragalactic Polarization (BICEP2) claimed a detection of the tensor-to-scalar ratio ($r$) of primordial fluctuation at $5\sigma$ confidence level. If it is true, this large and…

宇宙学与河外天体物理 · 物理学 2014-08-06 Yi Wang , Yin-Zhe Ma

Statistical isotropy (SI) has been one of the simplifying assumptions in cosmological model building. Experiments like WMAP and PLANCK are attempting to test this assumption by searching for specific signals in the Cosmic Microwave…

宇宙学与河外天体物理 · 物理学 2011-11-21 Aditya Rotti , Moumita Aich , Tarun Souradeep

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…

宇宙学与河外天体物理 · 物理学 2024-06-05 Oliver T. Oayda , Vasudev Mittal , Geraint F. Lewis , Tara Murphy

We introduce a new mathematical tool (a direction-dependent probe) to analyse the randomness of purported isotropic Gaussian random fields on the sphere. We apply the probe to assess the full-sky cosmic microwave background (CMB)…

宇宙学与河外天体物理 · 物理学 2020-06-29 J. Hamann , Q. T. Le Gia , I. H. Sloan , Y. G. Wang , R. S. Womersley

The largest temperature anisotropy in the cosmic microwave background (CMB) is the dipole, which has been measured with increasing accuracy for more than three decades, particularly with the Planck satellite. The simplest interpretation of…

宇宙学与河外天体物理 · 物理学 2021-01-04 Planck Collaboration , Y. Akrami , M. Ashdown , J. Aumont , C. Baccigalupi , M. Ballardini , A. J. Banday , R. B. Barreiro , N. Bartolo , S. Basak , K. Benabed , J. -P. Bernard , M. Bersanelli , P. Bielewicz , J. R. Bond , J. Borrill , F. R. Bouchet , C. Burigana , E. Calabrese , J. -F. Cardoso , B. Casaponsa , H. C. Chiang , C. Combet , D. Contreras , B. P. Crill , F. Cuttaia , P. de Bernardis , A. de Rosa , G. de Zotti , J. Delabrouille , E. Di Valentino , J. M. Diego , O. Doré , M. Douspis , X. Dupac , T. A. Enßlin , H. K. Eriksen , R. Fernandez-Cobos , F. Finelli , M. Frailis , E. Franceschi , A. Frolov , S. Galeotta , S. Galli , K. Ganga , R. T. Génova-Santos , M. Gerbino , J. González-Nuevo , K. M. Górski , A. Gruppuso , J. E. Gudmundsson , W. Handley , D. Herranz , E. Hivon , Z. Huang , A. H. Jaffe , W. C. Jones , E. Keihänen , R. Keskitalo , K. Kiiveri , J. Kim , T. S. Kisner , N. Krachmalnicoff , M. Kunz , H. Kurki-Suonio , J. -M. Lamarre , M. Lattanzi , C. R. Lawrence , M. Le Jeune , F. Levrier , M. Liguori , P. B. Lilje , V. Lindholm , M. López-Caniego , J. F. Macías-Pérez , D. Maino , N. Mandolesi , A. Marcos-Caballero , M. Maris , P. G. Martin , E. Martínez-González , S. Matarrese , N. Mauri , J. D. McEwen , A. Mennella , M. Migliaccio , D. Molinari , A. Moneti , L. Montier , G. Morgante , A. Moss , P. Natoli , L. Pagano , D. Paoletti , F. Perrotta , V. Pettorino , F. Piacentini , G. Polenta , J. P. Rachen , M. Reinecke , M. Remazeilles , A. Renzi , G. Rocha , C. Rosset , J. A. Rubiño-Martín , B. Ruiz-Granados , L. Salvati , M. Savelainen , D. Scott , C. Sirignano , G. Sirri , L. D. Spencer , R. M. Sullivan , R. Sunyaev , A. -S. Suur-Uski , J. A. Tauber , D. Tavagnacco , M. Tenti , L. Toffolatti , M. Tomasi , T. Trombetti , J. Valiviita , B. Van Tent , P. Vielva , F. Villa , N. Vittorio , I. K. Wehus , A. Zacchei , A. Zonca

We present a general method for Bayesian inference of the underlying covariance structure of random fields on a sphere. We employ the Bipolar Spherical Harmonic (BipoSH) representation of general covariance structure on the sphere. We…

宇宙学与河外天体物理 · 物理学 2015-11-04 Santanu Das , Benjamin D. Wandelt , Tarun Souradeep

Evidences for late-time acceleration of the Universe are provided by multiple probes, such as Type Ia supernovae, the cosmic microwave background (CMB) and large-scale structure (LSS). In this work, we focus on the integrated Sachs--Wolfe…

宇宙学与河外天体物理 · 物理学 2016-07-27 E. Moura Santos , F. C. Carvalho , M. Penna-Lima , C. P. Novaes , C. A. Wuensche

The recent measurements of the Cosmic Microwave Background anisotropies at arcminute angular scales performed by the ACT and SPT experiments are probing the damping regime of CMB fluctuations. The analysis of these datasets unexpectedly…

宇宙学与河外天体物理 · 物理学 2013-05-30 Eloisa Menegoni , Maria Archidiacono , Erminia Calabrese , Silvia Galli , C. J. A. P. Martins , Alessandro Melchiorri

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…

天体物理学 · 物理学 2015-06-24 V. Kolokotronis , M. Plionis , P. Coles , S. Borgani , L. Moscardini