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Related papers: A weak lensing view on primordial non-Gaussianitie…

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Using the 5 year WMAP data, we re-investigate claims of non-Gaussianities and asymmetries detected in local curvature statistics of the 1 year WMAP data. In Hansen et al 2004, it was found that the northern ecliptic hemisphere was…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Øystein Rudjord , Nicolaas E. Groeneboom , Frode K. Hansen , Paolo Cabella

We characterize the Cosmic Infrared Background (CIB)-lensing bispectrum which is one of the contributions to the three-point functions of Cosmic Microwave Background (CMB) maps in harmonic space. We show that the CIB-lensing bispectrum has…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 A. Curto , M. Tucci , M. Kunz , E. Martinez-Gonzalez

We performed a series of numerical experiments to quantify the sensitivity of the predictions for weak lensing statistics obtained in raytracing DM-only simulations, to two hyper-parameters that influence the accuracy as well as the…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-11 José Manuel Zorrilla Matilla , Stefan Waterval , Zoltán Haiman

We investigate the impact of non-Gaussian lensing deflections on measurements of the CMB lensing power spectrum. We find that the false assumption of their Gaussianity significantly biases these measurements in current and future…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-19 Vanessa Böhm , Blake D. Sherwin , Jia Liu , J. Colin Hill , Marcel Schmittfull , Toshiya Namikawa

We present a full forward-modeled $w$CDM analysis of the KiDS-1000 weak lensing maps using graph-convolutional neural networks (GCNN). Utilizing the $\texttt{CosmoGrid}$, a novel massive simulation suite spanning six different cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-21 Janis Fluri , Tomasz Kacprzak , Aurelien Lucchi , Aurel Schneider , Alexandre Refregier , Thomas Hofmann

Tighter constraints on measurements of primordial non-Gaussianity will allow the differentiation of inflationary scenarios. The cosmic microwave background bispectrum-the standard method of measuring the local non-Gaussianity-is limited by…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-15 Zahra Gomes , Stefano Camera , Matt J. Jarvis , Catherine Hale , José Fonseca

We investigate how well future large-scale radio surveys could measure different shapes of primordial non-Gaussianity; in particular we focus on angle-dependent non-Gaussianity arising from primordial anisotropic sources, whose bispectrum…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-22 Alvise Raccanelli , Maresuke Shiraishi , Nicola Bartolo , Daniele Bertacca , Michele Liguori , Sabino Matarrese , Ray P. Norris , David Parkinson

We study the correlations of the shear signal between triplets of sources in the Canada-France-Hawaii Lensing Survey (CFHTLenS) to probe cosmological parameters via the matter bispectrum. In contrast to previous studies, we adopted a…

The strong dependence of the large-scale dark matter halo bias on the (local) non-Gaussianity parameter, f_NL, offers a promising avenue towards constraining primordial non-Gaussianity with large-scale structure surveys. In this paper, we…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-14 Beth A. Reid , Licia Verde , Klaus Dolag , Sabino Matarrese , Lauro Moscardini

The possibility of detecting weak lensing effects from deep wide field imaging surveys has open new means of probing the large-scale structures of the Universe and measuring cosmological parameters. In this paper we present a systematic…

Astrophysics · Physics 2010-04-06 F. Bernardeau , L. van Waerbeke , Y. Mellier

We introduce an exact Bayesian approach to search for non-Gaussianity of local type in Cosmic Microwave Background (CMB) radiation data. Using simulated CMB temperature maps, the newly developed technique is compared against the…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-15 Franz Elsner , Benjamin D. Wandelt

We have detected non-Gaussian signatures in the VIRMOS-DESCART weak lensing survey from a measurement of the three-point shear correlation function, following the method developed by Bernardeau et al. (2002). We obtain a 2.4-sigma signal…

Astrophysics · Physics 2009-11-07 F. Bernardeau , Y. Mellier , L. van Waerbeke

The detection of primordial non-Gaussianity could provide a powerful means to test various inflationary scenarios. Although scale-invariant non-Gaussianity (often described by the $f_{NL}$ formalism) is currently best constrained by the…

Astrophysics · Physics 2009-06-23 Marilena LoVerde , Amber Miller , Sarah Shandera , Licia Verde

The coherent image distortions induced by weak gravitational lensing can be used to measure the power spectrum of density inhomogeneities in the universe. We present our on-going effort to detect this effect with the FIRST radio survey,…

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

The subject of this paper is the investigation of inflationary non-Gaussianities of the local type with extreme value statistics of the weak lensing convergence kappa. Specifically, we describe the influence of inflationary…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-08 Federica Capranico , Angelos Fotios Kalovidouris , Bjoern Malte Schaefer

Pinning down the total neutrino mass and the dark energy equation of state is a key aim for upcoming galaxy surveys. Weak lensing is a unique probe of the total matter distribution whose non-Gaussian statistics can be quantified by the…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-08 Aoife Boyle , Cora Uhlemann , Oliver Friedrich , Alexandre Barthelemy , Sandrine Codis , Francis Bernardeau , Carlo Giocoli , Marco Baldi

We study primordial non-Gaussian signatures in the redshift-space halo field on non-linear scales, using a quasi-maximum likelihood estimator based on optimally compressed power spectrum and modal bispectrum statistics. We train and…

Optical weak lensing surveys have become a powerful tool for precision cosmology, but remain subject to systematic effects that can severely bias cosmological parameter estimates if not carefully removed. We discuss the possibility of…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-22 Philip Bull , Ian Harrison , Eric Huff

Our view of the last-scattering surface in the cosmic microwave background (CMB) is obscured by secondary anisotropies, sourced by scattering, extragalactic emission and gravitational processes between recombination and observation. Whilst…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-10 William Coulton , Alexander Miranthis , Anthony Challinor