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Related papers: Constraining the Reionization History using Bayesi…

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The Vera Rubin Observatory, set to begin observations in mid-2024, will increase our discovery rate of supernovae to well over one million annually. There has been a significant push to develop new methodologies to identify, classify and…

High Energy Astrophysical Phenomena · Physics 2022-11-10 V. Ashley Villar

A yet undetected class of GW signals is represented by the close encounters between compact objects in highly-eccentric e~1 orbits, that can occur in binary systems formed in dense environments such as globular clusters. The expected…

General Relativity and Quantum Cosmology · Physics 2025-09-26 Federico De Santi , Massimiliano Razzano , Francesco Fidecaro , Luca Muccillo , Lucia Papalini , Barbara Patricelli

Exoplanet observations are currently analysed with Bayesian retrieval techniques. Due to the computational load of the models used, a compromise is needed between model complexity and computing time. Analysis of data from future facilities,…

Earth and Planetary Astrophysics · Physics 2022-06-29 Francisco Ardevol Martinez , Michiel Min , Inga Kamp , Paul I. Palmer

During the epoch of reionization (EoR), the 21-cm signal allows direct observation of the neutral hydrogen (HI) in the intergalactic medium (IGM). In the post-reionization era, this signal instead probes HI in galaxies, which traces the…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-20 Sambit K. Giri , Michele Bianco , Timothée Schaeffer , Ilian T. Iliev , Garrelt Mellema , Aurel Schneider

Stellar ages are critical building blocks of evolutionary models, but challenging to measure for low mass main sequence stars. An unexplored solution in this regime is the application of probabilistic machine learning methods to…

Solar and Stellar Astrophysics · Physics 2023-07-19 Phil Van-Lane , Joshua S. Speagle , Stephanie Douglas

(ABRIDGED)The rise of cosmic structure depends upon the statistical distribution of initial density fluctuations generated by inflation. While the simplest models predict an almost perfectly Gaussian distribution, more-general models…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Anson D'Aloisio , Jun Zhang , Paul R. Shapiro , Yi Mao

The properties of the first galaxies, expected to drive the Cosmic Dawn (CD) and the Epoch of Reionization (EoR), are encoded in the 3D structure of the cosmic 21-cm signal. Parameter inference from upcoming 21-cm observations promises to…

Astrophysics of Galaxies · Physics 2019-01-24 Jaehong Park , Andrei Mesinger , Bradley Greig , Nicolas Gillet

Normalizing Flows (NFs) are flexible explicit generative models that have been shown to accurately model complex real-world data distributions. However, their invertibility constraint imposes limitations on data distributions that reside on…

Computer Vision and Pattern Recognition · Computer Science 2022-08-19 Janis Postels , Martin Danelljan , Luc Van Gool , Federico Tombari

Convolutional neural networks (CNNs) have shown outstanding performance on image denoising with the help of large-scale datasets. Earlier methods naively trained a single CNN with many pairs of clean-noisy images. However, the conditional…

Image and Video Processing · Electrical Eng. & Systems 2021-04-05 Jae Woong Soh , Nam Ik Cho

Observations of the Epoch of Reionization (EoR) have the potential to answer long-standing questions of astrophysical interest regarding the nature of the first luminous sources and their effects on the intergalactic medium (IGM). We…

Normalizing Flows (NFs) describe a class of models that express a complex target distribution as the composition of a series of bijective transformations over a simpler base distribution. By limiting the space of candidate transformations…

Machine Learning · Computer Science 2023-09-11 Keegan Kelly , Lorena Piedras , Sukrit Rao , David Roth

Normalizing Flows (NFs) are universal density estimators based on Neural Networks. However, this universality is limited: the density's support needs to be diffeomorphic to a Euclidean space. In this paper, we propose a novel method to…

Machine Learning · Computer Science 2022-02-02 Christian Horvat , Jean-Pascal Pfister

Bayesian analysis has become an indispensable tool across many different cosmological fields including the study of gravitational waves, the Cosmic Microwave Background and the 21-cm signal from the Cosmic Dawn among other phenomena. The…

Instrumentation and Methods for Astrophysics · Physics 2023-12-19 Harry T. J. Bevins , William J. Handley , Pablo Lemos , Peter H. Sims , Eloy de Lera Acedo , Anastasia Fialkov , Justin Alsing

Recurrent neural networks (RNNs) are nonlinear dynamical models commonly used in the machine learning and dynamical systems literature to represent complex dynamical or sequential relationships between variables. More recently, as deep…

Methodology · Statistics 2018-02-08 Patrick L. McDermott , Christopher K. Wikle

The statistical properties of the primordial perturbations contain clues about the origins of those fluctuations. Although the Planck collaboration has recently obtained tight constraints on primordial non-gaussianity from cosmic microwave…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-09 Adam Lidz , Eric J. Baxter , Peter Adshead , Scott Dodelson

We present a machine learning approach using normalising flows for inferring cosmological parameters from gravitational wave events. Our methodology is general to any type of compact binary coalescence event and cosmological model and…

General Relativity and Quantum Cosmology · Physics 2023-10-26 Federico Stachurski , Christopher Messenger , Martin Hendry

Convolutional neural networks (CNNs) work well on large datasets. But labelled data is hard to collect, and in some applications larger amounts of data are not available. The problem then is how to use CNNs with small data -- as CNNs…

Machine Learning · Statistics 2016-01-19 Yarin Gal , Zoubin Ghahramani

The prospect of detecting the first galaxies by observing their impact on the intergalactic medium as they reionized it during the first billion years leads us to ask whether such indirect observations are capable of diagnosing which types…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Ilian T. Iliev , Garrelt Mellema , Paul R. Shapiro , Ue-Li Pen , Yi Mao , Jun Koda , Kyungjin Ahn

We present a detailed comparison of three different simulations of the epoch of reionization (EoR). The radiative transfer simulation (${\rm C}^2$-RAY) among them is our benchmark. Radiative transfer codes can produce realistic results, but…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-07 Suman Majumdar , Garrelt Mellema , Kanan K. Datta , Hannes Jensen , T. Roy Choudhury , Somnath Bharadwaj , Martina M. Friedrich

Neural networks are increasingly being used in a variety of settings to predict wind direction and speed, two of the most important factors for estimating the potential power output of a wind farm. However, these predictions are arguably of…

Atmospheric and Oceanic Physics · Physics 2022-06-22 Mariana C A Clare , Matthew D Piggott