English
Related papers

Related papers: A New Window on Primordial non-Gaussianity

200 papers

A measurement of primordial non-gaussianity will be of paramount importance to distinguish between different models of inflation. Cosmic microwave background (CMB) anisotropy observations have set unprecedented bounds on the non-gaussianity…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-14 Julian B. Muñoz , Yacine Ali-Haïmoud , Marc Kamionkowski

We investigate future constraints on primordial local-type non-Gaussianity from 21 cm angular power spectrum from minihalos. We particularly focus on the trispectrum of primordial curvature perturbations which are characterized by the…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-27 Toyokazu Sekiguchi , Tomo Takahashi , Hiroyuki Tashiro , Shuichiro Yokoyama

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

Under the presence of anisotropic sources in the inflationary era, the trispectrum of the primordial curvature perturbation has a very specific angular dependence between each wavevector that is distinguishable from the one encountered when…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-12 Maresuke Shiraishi , Nicola Bartolo , Michele Liguori

Detailed study of the scalar and tensor perturbation spectra can provide much information about the primordial fluctuation-generator, be it inflation or something else. The tensor perturbation spectrum may be observable through its…

Astrophysics · Physics 2007-05-23 L. Knox

The primordial non-Gaussianity of local type affects the clustering of dark matter halos, and the planned deep and wide photometric surveys are suitable for examining this class of non-Gaussianity. In our previous paper, we investigated the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Yoshitaka Takeuchi , Kiyotomo Ichiki , Takahiko Matsubara

Silk damping at redshifts 1.5 x 10^4 < z < 2 x 10^6 erases CMB anisotropies on scales corresponding to the comoving wavenumbers 8 < k < 10^4 Mpc^-1 (10^5 < \ell < 10^8). This dissipated energy is gained by the CMB monopole, creating…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-21 Rishi Khatri , Rashid A. Sunyaev

Primordial magnetic fields lead to non-Gaussian signals in the Cosmic Microwave Background (CMB) even at the lowest order, as magnetic stresses, and the temperature anisotropy they induce, depend quadratically on the magnetic field. In…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-03 T. R. Seshadri , Kandaswamy Subramanian

Diffusion damping of the cosmic microwave background (CMB) power spectrum results from imperfect photon-baryon coupling in the pre-recombination plasma. At redshift $5 \times 10^4 < z < 2 \times 10^6$, the plasma acquires an effective…

We present a set of formalisms for comparing, evolving and constraining primordial non-Gaussian models through the CMB bispectrum. We describe improved methods for efficient computation of the full CMB bispectrum for any general…

Astrophysics · Physics 2009-09-02 J. R. Fergusson , E. P. S. Shellard

Non-Gaussianity of the primordial density perturbations provides an important measure to constrain models of inflation. At cubic order the non-Gaussianity is captured by two parameters $\tau_{\rm NL}$ and $g_{\rm NL}$ that determine the…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-12 Chang Feng , Asantha Cooray , Joseph Smidt , Jon O'Bryan , Brian Keating , Donough Regan

A complete numerical calculation of the temperature anisotropies and the polarization of the cosmic microwave background (CMB) is presented for a non zero cross correlation of a stochastic magnetic field with the primordial curvature…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-15 Kerstin E. Kunze

A well-known route to form primordial black holes in the early universe relies on the existence of unusually large primordial curvature fluctuations, confined to a narrow range of wavelengths that would be too small to be constrained by…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-20 Devanshu Sharma , Julien Lesgourgues , Christian T. Byrnes

We propose a new mechanism of generating the $\mu$ distortion in cosmic microwave background (CMB) originated from primordial gravitational waves. Such $\mu$ distortion is generated by the damping of the temperature anisotropies through the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Atsuhisa Ota , Tomo Takahashi , Hiroyuki Tashiro , Masahide Yamaguchi

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

When constraining the primordial non-Gaussianity parameter f_NL with cosmic microwave background anisotropy maps, the bias resulting from the covariance between primordial non-Gaussianity and secondary non-Gaussianities to the estimator of…

Astrophysics · Physics 2008-11-26 Paolo Serra , Asantha Cooray

Primordial magnetic fields (PMFs) create a large squeezed-type non-Gaussianity in tensor perturbation, which generates non-Gaussian temperature fluctuations in the cosmic microwave background (CMB). We for the first time derive an…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-13 Maresuke Shiraishi , Toyokazu Sekiguchi

The primordial non-Gaussian parameter fNL has been shown to be scale-dependent in several models of inflation with a variable speed of sound. Starting from a simple ansatz for a scale-dependent amplitude of the primordial curvature…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-06 Emiliano Sefusatti , Michele Liguori , Amit P. S. Yadav , Mark G. Jackson , Enrico Pajer

We give new constraints on small-scale non-Gaussianity of primordial curvature perturbations by the use of anisotropies in acoustic reheating. Mixing of local thermal or local kinetic equilibrium systems with different temperatures yields a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Atsushi Naruko , Atsuhisa Ota , Masahide Yamaguchi

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