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Aims: We introduce a new deep-learning approach for the reconstruction of 3D dust density and temperature distributions from multi-wavelength dust emission observations on the scale of individual star-forming cloud cores (<0.2pc). Methods:…

The diffusion coefficient of heavy quarks in the deconfined medium is examined in this research using a deep convolutional neural network (CNN) trained with data from relativistic heavy ion collisions involving heavy flavor hadrons. The CNN…

Nuclear Theory · Physics 2023-11-22 Rui Guo , Yonghui Li , Baoyi Chen

We study chromospheric emission to understand the temperature stratification in the solar chromosphere. We observed the intensity profile of the CaIIH line in a quiet Sun region close to the disk center at the German Vacuum Tower Telescope.…

Astrophysics · Physics 2009-11-13 R. Rezaei , J. H. M. J. Bruls , W. Schmidt , C. Beck , W. Kalkofen , R. Schlichenmaier

We describe a novel end-to-end approach using Machine Learning to reconstruct the power spectrum of cosmological density perturbations at high redshift from observed quasar spectra. State-of-the-art cosmological simulations of structure…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-21 Maria Han Veiga , Xi Meng , Oleg Y. Gnedin , Nickolay Y. Gnedin , Xun Huan

Temperature field reconstruction is essential for analyzing satellite heat reliability. As a representative machine learning model, the deep convolutional neural network (DCNN) is a powerful tool for reconstructing the satellite temperature…

Machine Learning · Computer Science 2022-02-15 Xiaohu Zheng , Wen Yao , Zhiqiang Gong , Yunyang Zhang , Xiaoya Zhang

Learning powerful feature representations for image retrieval has always been a challenging task in the field of remote sensing. Traditional methods focus on extracting low-level hand-crafted features which are not only time-consuming but…

Computer Vision and Pattern Recognition · Computer Science 2017-05-22 Weixun Zhou , Shawn Newsam , Congmin Li , Zhenfeng Shao

Convolutional neural networks (CNNs) can potentially provide powerful tools for classifying and identifying patterns in climate and environmental data. However, because of the inherent complexities of such data, which are often…

Atmospheric and Oceanic Physics · Physics 2020-03-03 Ashesh Chattopadhyay , Pedram Hassanzadeh , Saba Pasha

A self-consistent formalism to jointly study cosmic reionization and thermal history of the IGM is presented. The model implements most of the relevant physics governing these processes, such as the inhomogeneous IGM density distribution,…

Astrophysics · Physics 2009-11-10 T. Roy Choudhury , A. Ferrara

The aim of this project is to recover the CMB anisotropies maps in temperature and polarized intensity by means of a deep convolutional neural network (CNN) which, after appropiate training, can remove the foregrounds from Planck and…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-29 A. Quintana-Estellés , B. Ruiz-Granados , P. Ruiz-Lapuente

Ionization balance in the intergalactic medium (IGM) is central to the interpretation of quasar absorption spectra, linking observed ionic columns to the underlying gas density, temperature, metallicity, and ionizing radiation field.…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-17 Bhaskar Arya , Kartick C. Sarkar , Shiv K. Sethi

We examine the temperature structure of the intergalactic medium IGM) surounding a hard radiation source, such as a Quasi-Stellar Object (QSO), as it responds to the onset of helium reionization by the source. We model the reionization…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-28 Avery Meiksin , Eric R. Tittley , Calum K. Brown

We investigate the hyperfine transition of $^{3}\mathrm{He}^{+}$ as a promising probe of the IGM during the final stages of helium reionization. Utilising the most recent helium reionization simulation, we generate three-dimensional maps of…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-17 Arghyadeep Basu , Benedetta Ciardi , Enrico Garaldi

The cosmic microwave background (CMB), carrying the inhomogeneous information of the very early universe, is of great significance for understanding the origin and evolution of our universe. However, observational CMB maps contain serious…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-12 Guo-Jian Wang , Hong-Liang Shi , Ye-Peng Yan , Jun-Qing Xia , Yan-Yun Zhao , Si-Yu Li , Jun-Feng Li

At redshifts z >~ 2, most of the baryons reside in the smooth intergalactic medium which is responsible for the low column density Lyman-alpha forest. This photoheated gas follows a tight temperature-density relation which introduces a…

Astrophysics · Physics 2009-10-31 Joop Schaye , Tom Theuns , Michael Rauch , George Efstathiou , Wallace L. W. Sargent

Recent years have brought more precise temperature measurements of the low-density intergalactic medium (IGM). These new measurements constrain the processes that heated the IGM, such as the reionization of H I and of He II. We present a…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-10 Phoebe R. Upton Sanderbeck , Anson D'Aloisio , Matthew J. McQuinn

The 21-cm brightness-temperature field of neutral hydrogen during the Epoch of Reionization and Cosmic Dawn is a rich source of cosmological and astrophysical information, primarily due to its significant non-Gaussian features. However, the…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-12 Bohdan Bidenko , Léon V. E. Koopmans , P. Daniel Meerburg

We use state-of-the-art hydrodynamical simulations combined with a 1D radiative transfer code to assess the extent to which the highly ionized regions observed close to z~6 quasars, which we refer to as near-zones, can constrain the…

Astrophysics · Physics 2008-11-26 James S. Bolton , Martin G. Haehnelt

Machine learning models have been employed to perform either physics-free data-driven or hybrid dynamical downscaling of climate data. Most of these implementations operate over relatively small downscaling factors because of the challenge…

Atmospheric and Oceanic Physics · Physics 2023-02-24 Daniel Getter , Julie Bessac , Johann Rudi , Yan Feng

This study aims to test a potential application of lognormal seminumerical simulations to recover the thermal parameters and Jeans length. This could be suitable for generating large number of synthetic spectra with various input data and…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-24 Tomas Ondro , Bhaskar Arya , Rudolf Galis

The incorporation of radiative transfer effects into cosmological hydrodynamical simulations is essential for understanding how the intergalactic medium (IGM) makes the transition from a neutral medium to one that is almost fully ionized.…

Astrophysics · Physics 2009-11-06 Aaron Sokasian , Tom Abel , Lars E. Hernquist