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Related papers: Probing Primordial Non-Gaussianity with Large-Scal…

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We propose a method to probe higher-order correlators of the primordial density field through the inhomogeneity of local non-Gaussian parameters, such as f_NL, measured within smaller patches of the sky. Correlators between n-point…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-28 Christian T. Byrnes , Sami Nurmi , Gianmassimo Tasinato , David Wands

Primordial non-Gaussianities provide an important test of inflationary models. Although the Planck CMB experiment has produced strong limits on non-Gaussianity on scales of clusters, there is still room for considerable non-Gaussianity on…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Mélanie Habouzit , Takahiro Nishimichi , Sébastien Peirani , Gary A. Mamon , Joseph Silk , Jacopo Chevallard

We investigate how well galaxy cluster number counts can constrain the primordial power spectrum. Measurements of the primary anisotropies in the cosmic microwave background (CMB) may be limited, by the presence of foregrounds from…

Astrophysics · Physics 2015-03-13 Teeraparb Chantavat , Christopher Gordon , Joseph Silk

We detect the cross-correlation between 2.7 million DESI quasar targets across 14,700 deg$^2$ (180 quasars deg$^{-2}$) and Planck 2018 CMB lensing at $\sim$30$\sigma$. We use the cross-correlation on very large scales to constrain local…

We present a novel approach to estimate the value of primordial non-Gaussianity ($f_{\rm NL}$) parameter directly from the Cosmic Microwave Background (CMB) maps using a convolutional neural network (CNN). While traditional methods rely on…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-26 Chandan G. Nagarajappa , Yin-Zhe Ma

Minkowski Functionals (MFs) are topological statistics that have become one of many standard tools used for investigating the statistical properties of cosmological random fields. They have found regular use in studies of departures from…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-20 Geraint Pratten , Dipak Munshi

We studied the effect of primordial non-Gaussianity with varied bispectrum shapes on the number counts of signal-to-noise peaks in wide field cosmic shear maps. The two cosmological contributions to this particular weak lensing statistic,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 M. Maturi , C. Fedeli , L. Moscardini

Primordial non-Gaussianity induces a scale-dependent bias in large scale structure (LSS) data, proportional to $f_{\rm NL}/k^2$ for the exact local ansatz. Recent work has shown that models of inflation that predict a large squeezed limit…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-03 Nishant Agarwal , Shirley Ho , Sarah Shandera

Forecasts and analyses of cosmological observations often rely on the assumption of a perfect theoretical model over a defined range of scales. We explore how model uncertainties and nuisance parameters in perturbative models of the matter…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-02 Tobias Baldauf , Mehrdad Mirbabayi , Marko Simonović , Matias Zaldarriaga

We derive a fast way for measuring primordial non-Gaussianity in a nearly full-sky map of the cosmic microwave background. We find a cubic combination of sky maps combining bispectrum configurations to capture a quadratic term in primordial…

Astrophysics · Physics 2009-11-07 Eiichiro Komatsu , David N. Spergel , Benjamin D. Wandelt

The proper general relativistic description of the observed galaxy power spectrum is substantially different from the standard Newtonian description on large scales, providing a unique opportunity to test general relativity on horizon…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-17 Jaiyul Yoo , Nico Hamaus , Uros Seljak , Matias Zaldarriaga

Primordial non-Gaussianity is a sensitive probe of the inflationary era, with a number of important theoretical targets living an order of magnitude beyond the reach of current CMB constraints. Maps of the large-scale structure of the…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-07 Daniel Baumann , Daniel Green

The simplest models of inflation predict small non-gaussianities and a featureless power spectrum. However, there exist a large number of well-motivated theoretical scenarios in which large non-gaussianties could be generated. In general,…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-11 Stefano Gariazzo , Laura Lopez-Honorez , Olga Mena

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

We study the large-scale bias parameter of cosmic voids with primordial non-Gaussian (PNG) initial conditions of the local type. In this scenario, the dark matter halo bias exhibits a characteristic scale dependence on large scales, which…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-03 Kwan Chuen Chan , Nico Hamaus , Matteo Biagetti

The evolution with time of the abundance of galaxy clusters is very sensitive to the statistical properties of the primordial density perturbations. It can thus be used to probe small deviations from Gaussianity in the initial conditions.…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 A. M. M. Trindade , P. P. Avelino , P. T. P. Viana

We know very little about primordial curvature perturbations on scales smaller than about a Mpc. Measurements of the mu-type distortion of the CMB spectrum provide the unique opportunity to probe these scales over the unexplored range from…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Enrico Pajer , Matias Zaldarriaga

We investigate how well the SPHEREx all-sky survey can constrain local primordial non-Gaussianity beyond the parameter $f_{\text{NL}}$ using galaxy power spectra. We forecast joint constraints on the parameters $f_{\text{NL}}$,…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-16 Charuhas Shiveshwarkar , Thejs Brinckmann , Marilena Loverde

The number density and correlation function of galaxies are two key quantities to characterize the distribution of the observed galaxy population. High-$z$ spectroscopic surveys, which usually involve complex target selection and are…

Astrophysics of Galaxies · Physics 2024-02-05 Jiacheng Meng , Cheng Li , Houjun Mo , Yangyao Chen , Kai Wang

Angular redshift fluctuations (ARF) are a new cosmological observable, recently proposed in the literature. It measures the 2D angular deviations of the average redshift of a given matter tracer under an input redshift shell. Since it…