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Related papers: Optimal constraint on g_NL from CMB

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We develop the first algorithm able to jointly compute the maximum {\it a posteriori} estimate of the Cosmic Microwave Background (CMB) temperature and polarization fields, the gravitational potential by which they are lensed, and…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-17 Marius Millea , Ethan Anderes , Benjamin D. Wandelt

We derive the linear correction term for needlet and wavelet estimators of the bispectrum and the non-linearity parameter fNL on cosmic microwave background radiation data. We show that on masked WMAP-like data with anisotropic noise, the…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-15 Simona Donzelli , Frode K. Hansen , Michele Liguori , Domenico Marinucci , Sabino Matarrese

We discuss the potential of the multi-tracer technique to improve observational constraints of the local primordial non-Gaussianity (PNG) parameter $f_{\rm NL}$ from the galaxy power spectrum. For two galaxy samples $A$ and $B$, the…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-20 Alexandre Barreira , Elisabeth Krause

Fast robust methods for calculating likelihoods from CMB observations on small scales generally rely on approximations based on a set of power spectrum estimators and their covariances. We investigate the optimality of these approximation,…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-06 Samira Hamimeche , Antony Lewis

Gaussian processes (GPs) are a popular model for spatially referenced data and allow descriptive statements, predictions at new locations, and simulation of new fields. Often a few parameters are sufficient to parameterize the covariance…

Machine Learning · Statistics 2021-01-01 Florian Gerber , Douglas W. Nychka

Numerical nonlinear algebra is applied to maximum likelihood estimation for Gaussian models defined by linear constraints on the covariance matrix. We examine the generic case as well as special models (e.g. Toeplitz, sparse, trees) that…

Computation · Statistics 2020-10-07 Bernd Sturmfels , Sascha Timme , Piotr Zwiernik

[Abridged] In recent works we have proposed two new large-angle non-Gaussianity indicators based on skewness and kurtosis of patches of CMB sky-sphere, and used them to find out significant deviation from Gaussianity in frequency bands and…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-15 A. Bernui , M. J. Reboucas

In this article, we describe a new estimate of the Cosmic Microwave Background (CMB) intensity map reconstructed by a joint analysis of the full Planck 2015 data (PR2) and WMAP nine-years. It provides more than a mere update of the CMB map…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-15 J. Bobin , F. Sureau , J-L Starck

The Planck CMB experiment has delivered the best constraints so far on primordial non-Gaussianity, ruling out early-Universe models of inflation that generate large non-Gaussianity. Although small improvements in the CMB constraints are…

We present a Bayesian calibration algorithm for CMB observations as implemented within the global end-to-end BeyondPlanck (BP) framework, and apply this to the Planck Low Frequency Instrument (LFI) data. Following the most recent Planck…

We explore constraints on dark energy and modified gravity with forecast 21cm intensity mapping measurements using the Effective Field Theory approach. We construct a realistic mock data set forecasting a low redshift 21cm signal power…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-19 Maria Berti , Marta Spinelli , Balakrishna S. Haridasu , Matteo Viel , Alessandra Silvestri

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

Estimation of the angular power spectrum is one of the important steps in Cosmic Microwave Background (CMB) data analysis. Here, we present a nonparametric estimate of the temperature angular power spectrum for the Planck 2013 CMB data. The…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Amir Aghamousa , Arman Shafieloo , Mihir Arjunwadkar , Tarun Souradeep

This article introduces a nonlinear generalized matrix factor model (GMFM) that allows for mixed-type variables, extending the scope of linear matrix factor models (LMFM) that are so far limited to handling continuous variables. We…

Methodology · Statistics 2024-09-17 Xinbing Kong , Tong Zhang

We investigate how much the constraints on the neutrino properties can be improved by combining the CMB, the photometric and spectroscopic galaxy redshift surveys which include the CMB lensing, galaxy lensing tomography, galaxy clustering…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Yoshitaka Takeuchi , Kenji Kadota

Constrained clustering leverages limited domain knowledge to improve clustering performance and interpretability, but incorporating pairwise must-link and cannot-link constraints is an NP-hard challenge, making global optimization…

Machine Learning · Computer Science 2025-10-28 Pedro Chumpitaz-Flores , My Duong , Cristobal Heredia , Kaixun Hua

We constrain the primordial non-Gaussianity parameter of the local model f_{NL} using the skewness power spectrum associated with the two-to-one cumulant correlator of cosmic microwave background temperature anisotropies. This…

Cosmology and Nongalactic Astrophysics · Physics 2010-07-22 Joseph Smidt , Alexandre Amblard , Paolo Serra , Asantha Cooray

We analyze the BOOMERanG 2003 (B03) 145 GHz temperature map to constrain the amplitude of a non Gaussian, primordial contribution to CMB fluctuations. We perform a pixel space analysis restricted to a portion of the map chosen in view of…

We present evidence for the detection of primordial non-Gaussianity of the local type (fNL), using the temperature information of the Cosmic Microwave Background (CMB) from the WMAP 3-year data. We employ the bispectrum estimator of…

Astrophysics · Physics 2008-11-26 Amit P. S. Yadav , Benjamin D. Wandelt

The recent emergence of deep learning has led to a great deal of work on designing supervised deep semantic segmentation algorithms. As in many tasks sufficient pixel-level labels are very difficult to obtain, we propose a method which…

Computer Vision and Pattern Recognition · Computer Science 2024-04-19 Matthias Schwab , Agnes Mayr , Markus Haltmeier