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Related papers: Primordial Non-Gaussianity from LAMOST Surveys

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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

The non-Gaussianity of initial perturbations provides information on the mechanism that generated primordial density fluctuations. The expected non-Gaussianity for slow-roll inflationary models is well below the ultimate detection level…

Astrophysics · Physics 2008-11-26 Asantha Cooray

Non-Gaussianity of the primordial curvature perturbations may arise from a variety of well motivated early Universe scenarios. In particular, inflationary theories with additional light degrees of freedom can generate a bispectrum that is…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-01 Peter Adshead , Avery J. Tishue

For the last decade, several probes have pointed to a cosmological tension between the amplitude of density fluctuations extrapolated from the cosmic microwave background within the standard cosmological model and the one encapsulated by…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-09 Clément Stahl , Benoit Famaey , Rodrigo Ibata , Oliver Hahn , Nicolas Martinet , Thomas Montandon

The cosmic microwave background (CMB) bispectrum is a well-known probe of the non-Gaussianity of primordial perturbations. Just as the intervening large-scale structure modifies the CMB angular power spectrum through weak gravitational…

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

We address the dual challenge of estimating deviations from Gaussianity arising in models of the Early Universe, whilst retaining information necessary to assess whether a detection of non-Gaussianity is primordial. We do this by…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Dipak Munshi , Alan Heavens

Inferring spatial curvature of the Universe with high-fidelity is a longstanding interest in cosmology. However, the strong degeneracy between dark energy equation-of-state parameter $w$ and curvature density parameter $\Omega_{\rm K}$ has…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-11 Yang Hu , Suhail Dhawan

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

Galaxy clustering data from current and upcoming large scale structure surveys can provide strong constraints on primordial non-Gaussianity through the scale-dependent halo bias. To fully exploit the information from galaxy surveys, optimal…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-05 Eva-Maria Mueller , Will J. Percival , Rossana Ruggeri

We present measurements of the bispectrum of dark matter halos in numerical simulations with non-Gaussian initial conditions of the local type. We show, in the first place, that the overall effect of primordial non-Gaussianity on the halo…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Emiliano Sefusatti , Martin Crocce , Vincent Desjacques

After the precise observations of the Cosmic Microwave Background (CMB) anisotropy power spectrum, attention is now being focused on the higher order statistics of the CMB anisotropies. Since linear evolution preserves the statistical…

Astrophysics · Physics 2009-11-10 Daniel Babich , Matias Zaldarriaga

Non-Gaussianities of dynamical origin are disentangled from primordial ones using the formalism of large deviation statistics with spherical collapse dynamics. This is achieved by relying on accurate analytical predictions for the one-point…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-27 Cora Uhlemann , Enrico Pajer , Christophe Pichon , Takahiro Nishimichi , Sandrine Codis , Francis Bernardeau

A major goal of ongoing and future cosmological surveys of the large-scale structure is to measure local type primordial non-Gaussianity in the galaxy power spectrum through the scale-dependent bias. General relativistic effects have been…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-05 Chris Addis , Sêcloka L. Guedezounme , Jessie Hammond , Chris Clarkson , Federico Montano , Stefano Camera , Sheean Jolicoeur , Roy Maartens

We forecast ability of dedicated 21 cm intensity mapping experiments to constraint primordial non-Gaussianity using power spectrum and bispectrum. We model the signal including the non-linear biasing expansion using a generalized halo model…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-30 Dionysios Karagiannis , Anže Slosar , Michele Liguori

Primordial Black Holes (PBH's) can form in the early Universe from the collapse of large density fluctuations. Tight observational limits on their abundance constrain the amplitude of the primordial fluctuations on very small scales which…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-20 Christian T. Byrnes , Edmund J. Copeland , Anne M. Green

We forecast the ability of bispectrum estimators to constrain primordial non-Gaussianity using future photometric galaxy redshift surveys. A full-sky survey with photometric redshift resolution of $\sigma_z/(1+z)=0.05$ in the redshift range…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-09 Julius Wons , Emanuela Dimastrogiovanni , Matteo Fasiello , Jan Hamann , Matthew C. Johnson

We compute the bispectrum for the \IRAS PSCz catalog and find that the galaxy distribution displays the characteristic signature of gravity. Assuming Gaussian initial conditions, we obtain galaxy biasing parameters…

Astrophysics · Physics 2009-10-31 Hume A. Feldman , Joshua A. Frieman , J. N. Fry , Roman Scoccimarro

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

We develop a new method to constraint primordial non-Gaussianities of the local kind using unclustered tracers of the Large Scale Structure. We show that in the limit of low noise, zero bias tracers yield large improvement over standard…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-12 Emanuele Castorina , Yu Feng , Uros Seljak , Francisco Villaescusa-Navarro

We investigate the relative sensitivities of several tests for deviations from Gaussianity in the primordial distribution of density perturbations. We consider models for non-Gaussianity that mimic that which comes from inflation as well as…

Astrophysics · Physics 2009-10-31 Licia Verde , Raul Jimenez , Marc Kamionkowski , Sabino Matarrese
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