English
Related papers

Related papers: Emulating radiation transport on cosmological scal…

200 papers

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

We compare the predictions of four different algorithms for the distribution of ionized gas during the Epoch of Reionization. These algorithms are all used to run a 100 Mpc/h simulation of reionization with the same initial conditions. Two…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Oliver Zahn , Andrei Mesinger , Matthew McQuinn , Hy Trac , Renyue Cen , Lars E. Hernquist

The observation of the redshifted 21-cm signal from the intergalactic medium will probe the epoch of reionization (EoR) with unprecedented detail. Various simulations are being developed and used to predict and understand the nature and…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-02 Prasad Rajesh Posture , Yashrajsinh Mahida , Suman Majumdar , Leon Noble

We present the first large-scale radiative transfer simulations of cosmic reionization, in a simulation volume of (100/h Mpc)^3, while at the same time capturing the dwarf galaxies which are primarily responsible for reionization. We…

We investigated the use of a U-Net convolutional neural network for denoising simulated medium-resolution spectroscopic observations of stars. Simulated spectra were generated under realistic observational conditions resembling the Subaru…

Instrumentation and Methods for Astrophysics · Physics 2025-04-04 Balázs Pál , László Dobos

We present a new method for modeling inhomogeneous cosmic reionization on large scales. Utilizing high-resolution radiation-hydrodynamic simulations with 2048^3 dark matter particles, 2048^3 gas cells, and 17 billion adaptive rays in a L =…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Nick Battaglia , Hy Trac , Renyue Cen , Abraham Loeb

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

We have developed a modular semi-numerical code that computes the time and spatially dependent ionization of neutral hydrogen (HI), neutral (HeI) and singly ionized helium (HeII) in the intergalactic medium (IGM). The model accounts for…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-02 Anne Hutter

The ability to recover MRI signal from noise is key to achieve fast acquisition, accurate quantification, and high image quality. Past work has shown convolutional neural networks can be used with abundant and paired low and high-SNR images…

The semi-airborne transient electromagnetic method (SATEM) is capable of conducting rapid surveys over large-scale and hard-to-reach areas. However, the acquired signals are often contaminated by complex noise, which can compromise the…

Machine Learning · Computer Science 2025-03-31 Shuang Wang , Ming Guo , Xuben Wang , Fei Deng , Lifeng Mao , Bin Wang , Wenlong Gao

Next-generation 21cm observations will enable imaging of reionization on very large scales. These images will contain more astrophysical and cosmological information than the power spectrum, and hence providing an alternative way to…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-27 Sultan Hassan , Adrian Liu , Saul Kohn , James E. Aguirre , Paul La Plante , Adam Lidz

Next generation radio experiments such as LOFAR, HERA and SKA are expected to probe the Epoch of Reionization and claim a first direct detection of the cosmic 21cm signal within the next decade. Data volumes will be enormous and can thus…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-03 Claude J Schmit , Jonathan R Pritchard

Large-scale reionization simulations are described which combine the results of cosmological N-body simulations that model the evolving density and velocity fields and identify the galactic halo sources, with ray-tracing radiative transfer…

While limited to low spatial resolution, the next generation low-frequency radio interferometers that target 21 cm observations during the era of reionization and prior will have instantaneous fields-of-view that are many tens of square…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 M. G. Santos , L. Ferramacho , M. B. Silva , A. Amblard , A. Cooray

We present a method for extracting the expected cosmological 21-cm signal from the epoch of reionization, taking into account contaminating radiations and random instrumental noise. The method is based on the maximum a-posteriori…

Astrophysics · Physics 2008-12-21 Liron Gleser , Adi Nusser , Andrew J. Benson

Herein, we present a deep-learning technique for reconstructing the dark-matter density field from the redshift-space distribution of dark-matter halos. We built a UNet-architecture neural network and trained it using the COmoving…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-21 Zitong Wang , Feng Shi , Xiaohu Yang , Qingyang Li , Yanming Liu , Xiaoping Li

Efficient and accurate simulations of the reionization epoch are crucial to exploring the vast uncharted parameter space that will soon be constrained by measurements of the 21 cm power spectrum. One of these parameters, $R_{\rm max}$, is…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-20 Frederick B. Davies , Steven R. Furlanetto

Initial density distribution provides a basis for understanding the complete evolution of cosmological density fluctuations. While reconstruction in our local Universe exploits the observations of galaxy surveys with large volumes,…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-28 Meng Zhou , Yi Mao

A deep convolutional neural network has been developed to denoise atomic-resolution TEM image datasets of nanoparticles acquired using direct electron counting detectors, for applications where the image signal is severely limited by shot…

We propose a UNet-based deep learning model to reconstruct the real-space dark matter (DM) velocity field from the redshift-space distribution of sparse DM halos. Using various statistical measures, we show that the reconstructed velocity…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-26 Xu Xiao , Jiacheng Ding , XiaoLin Luo , Sun Ke Lan , Liang Xiao , Shuai Liu , Xin Wang , Le Zhang , Xiao-Dong Li
‹ Prev 1 2 3 10 Next ›