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Related papers: Statistical anisotropy in CMB spectral distortions

200 papers

We report on a measurement of the angular power spectrum of the anisotropy in the Cosmic Microwave Background. The anisotropy is measured in 23 different multipole bands from l=54 (~3 deg) to l=404 (~0.45 deg) and in 6 frequency bands from…

Astrophysics · Physics 2009-10-28 C. B. Netterfield , M. J. Devlin , N. Jarosik , L. Page , E. J. Wollack

Several anomalies have been identified which may imply a breakdown of the statistical isotropy of the cosmic microwave background (CMB). In particular, an anomalous alignment of the quadrupole and octopole and a hemispherical power…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Hiranya V. Peiris , Tristan L. Smith

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.…

We test anisotropic dark energy models with the 7-year WMAP temperature observations data. In the presence of imperfect sources, due to large-scale gradients or anisotropies in the dark energy field, the CMB sky will be distorted…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-08 Magnus J. Axelsson , Frode K. Hansen , Tomi Koivisto , David F. Mota

Anisotropies in distortions to the frequency spectrum of the cosmic microwave background (CMB) can be created through spatially varying heating processes in the early Universe. For instance, the dissipation of small-scale acoustic modes…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-25 Jens Chluba , Emanuela Dimastrogiovanni , Mustafa A. Amin , Marc Kamionkowski

The damping of primordial perturbations at small scales gives rise to distortions of the cosmic microwave background (CMB). Here, the dependence of the distortion on the different types of cosmological initial conditions is explored,…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-18 Jens Chluba , Daniel Grin

We constrain several models of the early Universe that predict a statistical anisotropy of the cosmic microwave background (CMB) sky. We make use of WMAP9 maps deconvolved with beam asymmetries. As compared to previous releases of WMAP…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-03 Sabir Ramazanov , Grigory Rubtsov

Observations from the first flight of the Medium Scale Anisotropy Measurement (MSAM) are analyzed to place limits on Gaussian fluctuations in the Cosmic Microwave Background Radiation (CMBR). This instrument chops a 30\arcmin\ beam in a 3…

The CMB angular temperature fluctuations observed by COBE and WMAP enable us to place a lower limit on the spectral distortions of the CMB at any angular scale. These distortions are connected with the simple fact, that the superposition of…

Astrophysics · Physics 2009-11-10 J. Chluba , R. A. Sunyaev

Results are reported from the first flight of a new balloon-borne instrument, BAM (Balloon-borne Anisotropy Measurement), designed to search for cosmic microwave background (CMB) anisotropy. The instrument uses a cryogenic differential…

Astrophysics · Physics 2007-05-23 G. S. Tucker , H. P. Gush , M. Halpern , I. Shinkoda , W. Towlson

In the near future, observations of the cosmic microwave background (CMB) anisotropies will provide accurate determinations of many fundamental cosmological parameters. In this paper, we analyse degeneracies among cosmological parameters to…

Astrophysics · Physics 2009-10-30 G. Efstathiou , J. R. Bond

We develop a linear perturbation theory for the spectral $y$-distortions of the cosmic microwave background (CMB). The $y$-distortions generated during the recombination epoch are usually negligible because the energy transfer due to the…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-10 Taku Haga , Keisuke Inomata , Atsuhisa Ota , Andrea Ravenni

The weak lensing effect on the cosmic microwave background (CMB) induces distortions in spatial pattern of CMB anisotropies, and statistical properties of CMB anisotropies become a weakly non-Gaussian field. We first summarize the weak…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-17 Toshiya Namikawa

Measurements of the cosmic microwave background (CMB) spectral distortions (SDs) will open a new window on the very early universe, providing new information complementary to that gathered from CMB temperature and polarization anisotropies.…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-12 Hao Fu , Matteo Lucca , Silvia Galli , Elia S. Battistelli , Deanna C. Hooper , Julien Lesgourgues , Nils Schöneberg

We compare the latest observations of Cosmic Microwave Background (CMB) Anisotropies with the theoretical predictions of the standard scenario of structure formation. Assuming a primordial power spectrum of adiabatic perturbations we found…

Astrophysics · Physics 2009-11-07 Alessandro Melchiorri , Carolina Odman

Cosmic microwave background (CMB) anisotropy may result from both scalar and tensor perturbations. For a sufficiently narrow range of angular scales, CMB perturbations can be characterized by four parameters. Results from the Cosmic…

Astrophysics · Physics 2009-10-22 Scott Dodelson , Lloyd Knox , Edward W. Kolb

The most general homogeneous and isotropic statistical ensemble of linear scalar perturbations which are regular at early times, in a universe with only photons, baryons, neutrinos, and a cold dark matter (CDM) component, is described by a…

Astrophysics · Physics 2009-10-31 Martin Bucher , Kavilan Moodley , Neil Turok

Since the discovery of the Cosmic Microwave Background (CMB) in 1965, characterization of the CMB anisotropy angular power spectrum has become somewhat of a holy grail for experimental cosmology. Because CMB anisotropy measurements are…

Astrophysics · Physics 2017-08-23 A. D. Miller

The standard models of inflation predict statistically homogeneous and isotropic primordial fluc- tuations, which should be tested by observations. In this paper we test the statistical isotropy of the mean of the CMB temperature…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Daichi Kashino , Kiyotomo Ichiki , Tsutomu T. Takeuchi

We propose a new formulation to calculate the Cosmic Microwave Background (CMB) spectrum in the Randall Sundrum two-branes model based on recent progresses in solving the bulk geometry using a low energy approximation. The evolution of the…

Astrophysics · Physics 2009-11-07 Kazuya Koyama