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Primordial black holes (PBHs) would induce non-Gaussianity in the cosmic microwave background (CMB) by sourcing recombination perturbations spatially modulated by relative velocities between PBHs and the baryons they accrete. The leading…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-11 Trey W. Jensen , Yacine Ali-Haïmoud

Recent second-order perturbation computations have provided an accurate prediction for the primordial gravitational potential $\Phi(x)$ in scenarios in which cosmological perturbations are generated either during or after inflation. This…

Astrophysics · Physics 2008-11-26 M. Liguori , F. K. Hansen , E. Komatsu , S. Matarrese , A. Riotto

The distribution of the polarization of the Cosmic Microwave Background (CMB) in the sky is determined by the hypothesis of random Gaussian distribution of the primordial density perturbations. This hypotheses is well motivated by the…

Astrophysics · Physics 2009-10-30 P. D. Naselsky , D. I. Novikov

We review in a pedagogical way the present status of the impact of non-Gaussianity (NG) on the Cosmic Microwave Background (CMB) anisotropies. We first show how to set the initial conditions at second-order for the (gauge invariant) CMB…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 N. Bartolo , S. Matarrese , A. Riotto

We calculate the CMB $\mu$-distortion and the angular power spectrum of its cross-correlation with the temperature anisotropy in the presence of the non-Gaussian neutrino isocurvature density (NID) mode. While the pure Gaussian NID…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Atsuhisa Ota , Toyokazu Sekiguchi , Yuichiro Tada , Shuichiro Yokoyama

The peculiar motion of an observer with respect to the CMB rest frame induces a deflection in the arrival direction of the observed photons (also known as CMB aberration) and a Doppler shift in the measured photon frequencies. As a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Riccardo Catena , Michele Liguori , Alessio Notari , Alessandro Renzi

We examine the contribution of tensor modes, in addition to the dominant scalar ones, on the temperature anisotropies of the cosmic microwave background (CMB). To this end, we analyze in detail the temperature two-point angular correlation…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-06 Miguel-Angel Sanchis-Lozano , Veronica Sanz

Some peculiar features found in the angular distribution of the cosmic microwave background (CMB) measured by the Wilkinson Microwave Anisotropy Probe (WMAP) deserve further investigation. Among these peculiar features, is the quadrant…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-01 Larissa Santos , Paolo Cabella , Thyrso Villela , Amedeo Balbi , Nicola Vittorio , Carlos Alexandre Wuensche

In this paper, we investigate the utility of Minkowski Functionals as a probe of cold/hot disk-like structures in the CMB. In order to construct an accurate estimator, we resolve a long-standing issue with the use of Minkowski Functionals…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Eugene A. Lim , Dennis Simon

We study the covariance in the angular power spectrum estimates of CMB fluctuations when the primordial fluctuations are non-Gaussian. The non-Gaussian covariance comes from a nonzero connected four-point correlation function -- or the…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-07 Saroj Adhikari , Dragan Huterer

The spectral variation of the cosmic microwave background (CMB) as observed by WMAP was tested using foreground reduced WMAP5 data, by producing subtraction maps at the 1$^\circ$ angular resolution between the two cosmological bands of V…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Bi-Zhu Jiang , Richard Lieu , Shuang-Nan Zhang , Bart Wakker

The measurements of the statistical properties of the Cosmic Microwave Background (CMB) fluctuations enable us to probe the physics of the very early Universe especially at the epoch of inflation. A particular interest lays on the detection…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-07 S. Pires , S. Plaszczynski , A. Lavabre

Angular power spectra of temperature anisotropies and polarization of the cosmic microwave background (CMB) as well as the linear matter power spectra are calculated for models with three light neutrinos with non-thermal phase-space…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-24 Kerstin E. Kunze

Minkowski Tensors are tensorial generalizations of the scalar Minkowski Functionals. Due to their tensorial nature they contain additional morphological information of structures, in particular about shape and alignment, in comparison to…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-09 Joby P. K. , Pravabati Chingangbam , Tuhin Ghosh , Vidhya Ganesan , Ravikumar C. D

Quantum gravity effects are expected to modify the primordial density fluctuations produced during inflation and leave their imprint on the cosmic microwave background observed today. We present a new analysis discussing whether these…

Astrophysics · Physics 2008-12-18 Nicolaas E. Groeneboom , Oystein Elgaroy

We study the angular distribution of temperature fluctuations in the cosmic microwave background (CMB) to probe the statistical isotropy of the universe by using precise full-sky CMB data with a model-independent approach. We investigated…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-01 C. E. Kester , A. Bernui , W. S. Hipólito-Ricaldi

The study of the angular power spectrum of Cosmic Microwave Background (CMB) anisotropies, both in intensity and in polarisation, has led to the tightest constraints on cosmological parameters. However, this statistical quantity is not…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-08 Javier Carrón Duque , Alessandro Carones , Domenico Marinucci , Marina Migliaccio , Nicola Vittorio

We explore a systematic approach to the analysis of primordial non-Gaussianity using fluctuations in temperature and polarization of the Cosmic Microwave Background (CMB). Following Munshi & Heavens (2009), we define a set of power-spectra…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Dipak Munshi , Peter Coles , Asantha Cooray , Alan Heavens , Joseph Smidt

We use the statistics of regions above or below a temperature threshold (excursion sets) to study the cosmic microwave background (CMB) anisotropy in models with primordial non-Gaussianity of the local type. By computing the full-sky…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Graziano Rossi , Pravabati Chingangbam , Changbom Park

The Planck CMB experiment has delivered the best constraints so far on primordial non-Gaussianity, ruling out early-Universe models of inflation that generate large non-Gaussianity. Although small improvements in the CMB constraints are…

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