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The breakdown of statistical homogeneity and isotropy of cosmic perturbations is a generic feature of ultra large scale structure of the cosmos, in particular, of non trivial cosmic topology. The statistical isotropy (SI) of the Cosmic…

Astrophysics · Physics 2008-11-26 Tarun Souradeep , Amir Hajian

There is enormous potential to advance cosmology from statistical characterizations of cosmic microwave background sky maps. The angular power spectrum of the microwave anisotropy is a particularly important statistic. Existing algorithms…

Astrophysics · Physics 2009-10-30 Siang Peng Oh , David N. Spergel , Gary Hinshaw

We test the statistical isotropy (SI) of the $E$-mode polarization of the Cosmic Microwave Background (CMB) radiation observed by the Planck satellite using two statistics, namely, the $\alpha$ estimator that is derived from the contour…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-11 Joby P. Kochappan , Aparajita Sen , Tuhin Ghosh , Pravabati Chingangbam , Soumen Basak

Large-scale magnetic fields affect the scalar modes of the geometry whose ultimate effect is to determine the anisotropies of the Cosmic Microwave Background (CMB in what follows). For the first time, a consistent numerical approach to the…

Astrophysics · Physics 2010-04-29 Massimo Giovannini , Kerstin E. Kunze

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.…

Understanding the statistical properties of synchrotron emission from our Galaxy is valuable from the perspective of observations targeting signals of cosmological origin, as well as for understanding physical processes in our Galaxy. In…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-18 Fazlu Rahman , Pravabati Chingangbam , Tuhin Ghosh

Parity violating extensions of the standard electromagnetic theory cause in vacuo rotation of the plane of polarization of propagating photons. This effect, also known as cosmic birefringence, impacts the cosmic microwave background (CMB)…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-14 Planck Collaboration , N. Aghanim , 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 , L. Bonavera , J. R. Bond , J. Borrill , F. R. Bouchet , C. Burigana , E. Calabrese , J. -F. Cardoso , J. Carron , H. C. Chiang , L. P. L. Colombo , B. Comis , D. Contreras , F. Couchot , A. Coulais , B. P. Crill , A. Curto , F. Cuttaia , P. de Bernardis , A. de Rosa , G. de Zotti , J. Delabrouille , F. -X. Désert , E. Di Valentino , C. Dickinson , J. M. Diego , O. Doré , A. Ducout , X. Dupac , S. Dusini , F. Elsner , T. A. Enßlin , H. K. Eriksen , Y. Fantaye , F. Finelli , F. Forastieri , M. Frailis , E. Franceschi , A. Frolov , S. Galeotta , S. Galli , K. Ganga , R. T. Génova-Santos , M. Gerbino , Y. Giraud-Héraud , J. González-Nuevo , K. M. Górski , A. Gruppuso , J. E. Gudmundsson , F. K. Hansen , S. Henrot-Versillé , D. Herranz , E. Hivon , Z. Huang , A. H. Jaffe , W. C. Jones , E. Keihänen , R. Keskitalo , K. Kiiveri , N. Krachmalnicoff , M. Kunz , H. Kurki-Suonio , J. -M. Lamarre , M. Langer , A. Lasenby , M. Lattanzi , C. R. Lawrence , M. Le Jeune , J. P. Leahy , F. Levrier , M. Liguori , P. B. Lilje , V. Lindholm , M. López-Caniego , Y. -Z. Ma , J. F. Macías-Pérez , G. Maggio , D. Maino , N. Mandolesi , M. Maris , P. G. Martin , E. Martínez-González , S. Matarrese , N. Mauri , J. D. McEwen , P. R. Meinhold , A. Melchiorri , A. Mennella , M. Migliaccio , M. -A. Miville-Deschênes , D. Molinari , A. Moneti , G. Morgante , A. Moss , P. Natoli , L. Pagano , D. Paoletti , G. Patanchon , L. Patrizii , L. Perotto , V. Pettorino , F. Piacentini , L. Polastri , G. Polenta , J. P. Rachen , B. Racine , M. Reinecke , M. Remazeilles , A. Renzi , G. Rocha , C. Rosset , M. Rossetti , G. Roudier , J. A. Rubiño-Martín , B. Ruiz-Granados , M. Sandri , M. Savelainen , D. Scott , C. Sirignano , G. Sirri , L. D. Spencer , A. -S. Suur-Uski , J. A. Tauber , D. Tavagnacco , M. Tenti , L. Toffolatti , M. Tomasi , M. Tristram , T. Trombetti , J. Valiviita , F. Van Tent , P. Vielva , F. Villa , N. Vittorio , B. D. Wandelt , I. K. Wehus , A. Zacchei , A. Zonca

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)…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-29 J. Hamann , Q. T. Le Gia , I. H. Sloan , Y. G. Wang , R. S. Womersley

We investigate a possibility of constraining statistical anisotropies of the primordial tensor perturbations by using future observations for the Cosmic Microwave Background (CMB) B-mode polarization. By parameterizing a…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-24 Takashi Hiramatsu , Shuichiro Yokoyama , Tomohiro Fujita , Ippei Obata

Polarization induced by cosmological scalar perturbations leads to a typical anisotropy pattern, which can best be analyzed in Fourier domain. This allows one to unambiguously distinguish cosmological signal of polarization from other…

Astrophysics · Physics 2009-10-28 Uros Seljak

Much attention has been given to the problem of estimating cosmological parameters from the $C_l$ measured by future experiments. Many of the approaches which are being used either invoke poorly controlled approximations or are…

Astrophysics · Physics 2007-05-23 Benjamin D. Wandelt , Eric Hivon , Krzysztof M. Gorski

The polarization of the Cosmic Microwave Background (CMB)is a powerful observational tool at hand for modern cosmology. It allows to break the degeneracy of fundamental cosmological parameters one cannot obtain using only anisotropy data…

Astrophysics · Physics 2007-05-23 M. V. Sazhin , G. Sironi , O. S. Khovanskaya

We present a formalism for analyzing a full-sky temperature and polarization map of the cosmic microwave background. Temperature maps are analyzed by expanding over the set of spherical harmonics to give multipole moments of the two-point…

Astrophysics · Physics 2009-10-28 Marc Kamionkowski , Arthur Kosowsky , Albert Stebbins

Measurements of the cosmic microwave background (CMB) allow high precision observation of the Last Scattering Surface at redshift $z\sim$1100. After the success of the NASA satellite COBE, that in 1992 provided the first detection of the…

Statistical Isotropy of the Cosmic Microwave Background (CMB) radiation has been studied and debated extensively in recent years. Under this assumption, the hot spots and cold spots of the CMB are expected to be uniformly distributed over a…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-14 Md Ishaque Khan , Rajib Saha

We analyze the spectrum of cosmic microwave background (CMB) anisotropies in the timescape cosmology: a potentially viable alternative to homogeneous isotropic cosmologies without dark energy. We exploit the fact that the timescape…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-18 M. Ahsan Nazer , David L. Wiltshire

The role of cosmic microwave background (CMB) polarisation data in constraining the presence of primordial isocurvature modes is examined. While the MAP satellite mission will be unable to simultaneously constrain isocurvature modes and…

Astrophysics · Physics 2009-10-31 M Bucher , K Moodley , N Turok

The Planck experiment will soon provide a very accurate measurement of Cosmic Microwave Background anisotropies. This will let cosmologists determine most of the cosmological parameters with unprecedented accuracy. Future experiments will…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-24 Silvia Galli , Matteo Martinelli , Alessandro Melchiorri , Luca Pagano , Blake D. Sherwin , David N. Spergel

We propose a novel representation of cosmic microwave anisotropy maps, where each multipole order l is represented by l unit vectors pointing in directions on the sky and an overall magnitude. These "multipole vectors and scalars" transform…

Astrophysics · Physics 2008-11-26 C. J. Copi , D. Huterer , G. D. Starkman

Polarization results from the Cosmic Anisotropy Polarization MAPper (CAPMAP) experiment are reported. These are based upon 433 hours, after cuts, observing a 2 square degree patch around the North Celestial Pole (NCP) with four 90 GHz…

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