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Related papers: Probing Primordial Non-Gaussianity with Weak Lensi…

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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 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

We study the impact of the cosmological parameters uncertainties on the measurements of primordial non-Gaussianity through the large-scale non-Gaussian halo bias effect. While this is not expected to be an issue for the standard LCDM model,…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-13 Carmelita Carbone , Olga Mena , Licia Verde

We present new constraints on the local-type primordial non-Gaussianity parameter, $f_\mathrm{NL}^\mathrm{local}$, through analysis of the scale-dependent bias effect on the cosmic infrared background (CIB). To avoid biases from galactic…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-06 Joseph Thornton , Fiona McCarthy , Carmen Embil Villagra , Blake D. Sherwin

We present a tomographic cosmological weak lensing analysis of the HST COSMOS Survey. Applying our lensing-optimized data reduction, principal component interpolation for the ACS PSF, and improved modelling of charge-transfer inefficiency,…

The NRAO VLA Sky Survey (NVSS) is the only dataset that allows an accurate determination of the auto-correlation function (ACF) on angular scales of several degrees for Active Galactic Nuclei (AGNs) at typical redshifts $z \simeq 1$.…

Cosmology and Nongalactic Astrophysics · Physics 2010-06-11 Jun-Qing Xia , Matteo Viel , Carlo Baccigalupi , Gianfranco De Zotti , Sabino Matarrese , Licia Verde

The characteristic signatures of massive neutrinos on large-scale structure (LSS), if fully captured, can be used to put a stringent constraint on their mass sum, $M_{\nu}$. Previous work utilizing N-body simulations has shown the Minkowski…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-19 Wei Liu , Aoxiang Jiang , Wenjuan Fang

Next-generation cosmological surveys will observe larger cosmic volumes than ever before, enabling us to access information on the primordial Universe, as well as on relativistic effects. We consider forthcoming 21cm intensity mapping…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-08 Jan-Albert Viljoen , José Fonseca , Roy Maartens

The next generation of CMB experiments should get a better handle on cosmological parameters by mapping the weak lensing deflection field, which is separable from primary anisotropies thanks to the non-Gaussianity induced by lensing.…

Astrophysics · Physics 2009-11-10 Julien Lesgourgues , Michele Liguori , Sabino Matarrese , Antonio Riotto

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

We present an upgraded combined estimator, based on Minkowski Functionals and Neural Networks, with excellent performance in detecting primordial non-Gaussianity in simulated maps that also contain a weighted mixture of Galactic…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-07 C. P. Novaes , A. Bernui , I. S. Ferreira , C. A. Wuensche

We study the impact of baryonic physics on cosmological parameter estimation with weak lensing surveys. We run a set of cosmological hydrodynamics simulations with different galaxy formation models. We then perform ray-tracing simulations…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-29 Ken Osato , Masato Shirasaki , Naoki Yoshida

We apply the multi-tracer technique to test the possibility of improved constraints on the amplitude of local primordial non-Gaussianity, $f_{\mathrm{NL}}$, in the cosmic large-scale structure. A precise measurement of $f_{\mathrm{NL}}$ is…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-28 Matilde Barberi Squarotti , Stefano Camera , Roy Maartens

The statistical property of the weak lensing fields is studied quantitatively using the ray-tracing simulations. Motivated by the empirical lognormal model that characterizes the probability distribution function(PDF) of the…

Astrophysics · Physics 2009-11-07 A. Taruya , M. Takada , T. Hamana , I. Kayo , T. Futamase

The identification of non-Gaussian signatures in cosmic microwave background (CMB) temperature maps is one of the main cosmological challenges today. We propose and investigate altenative methods to analyse CMB maps. Using the technique of…

Astrophysics · Physics 2009-11-07 C. Raeth , P. Schuecker

Local primordial non-Gaussianity (LPNG) couples long-wavelength cosmological fluctuations to the short-wavelength behavior of galaxies. This coupling is encoded in bias parameters including $b_{\phi}$ and $b_{\delta\phi}$ at linear and…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-11 James M. Sullivan , Shi-Fan Chen

We investigate the potential of weak gravitational lensing maps to differentiate between distinct cosmological models, considering cosmic variance due to a limited map extension and the presence of noise. We introduce a measure of the…

Astrophysics · Physics 2009-11-07 Antonio Guimarães

Key non-Gaussian properties of cosmological fields can be captured by their one-point statistics, providing a complement to two-point statistical measurements from power spectra or correlation functions. Large deviation theory can robustly…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-31 Aoife Boyle , Alexandre Barthelemy , Sandrine Codis , Cora Uhlemann , Oliver Friedrich

The recent progress in obtaining larger and deeper galaxy catalogues is of fundamental importance for cosmological studies, especially to robustly measure the large scale density fluctuations in the Universe. The present work uses the…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-23 Camila P. Novaes , Armando Bernui , Henrique S. Xavier , Gabriela A. Marques

We derive robust constraints on primordial non-Gaussianity (PNG) using the clustering of 800,000 photometric quasars from the Sloan Digital Sky Survey in the redshift range $0.5<z<3.5$. These measurements rely on the novel technique of {\it…

Cosmology and Nongalactic Astrophysics · Physics 2015-02-11 Boris Leistedt , Hiranya V. Peiris , Nina Roth
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