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The information regarding how the intergalactic medium is reionized by astrophysical sources is contained in the tomographic three-dimensional 21 cm images from the epoch of reionization. In Zhao et al. (2022a) ("Paper I"), we demonstrated…

Instrumentation and Methods for Astrophysics · Physics 2024-09-12 Xiaosheng Zhao , Yi Mao , Shifan Zuo , Benjamin D. Wandelt

The mean free path of ionizing photons, $\lambda_{\rm mfp}$, is a key factor in the photoionization of the intergalactic medium (IGM). At $z \gtrsim 5$, however, $\lambda_{\rm mfp}$ may be short enough that measurements towards QSOs are…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-29 George D. Becker , Anson D'Aloisio , Holly M. Christenson , Yongda Zhu , Gábor Worseck , James S. Bolton

Computed tomography (CT) involves a patient's exposure to ionizing radiation. To reduce the radiation dose, we can either lower the X-ray photon count or down-sample projection views. However, either of the ways often compromises image…

Image and Video Processing · Electrical Eng. & Systems 2023-10-12 Wenjun Xia , Yongyi Shi , Chuang Niu , Wenxiang Cong , Ge Wang

We describe a new, faster implicit algorithm for solving the radiation hydrodynamics equations in the flux-limited diffusion approximation for smoothed particle hydrodynamics. This improves on the method elucidated in Whitehouse & Bate by…

Astrophysics · Physics 2009-11-13 Stuart C. Whitehouse , Matthew R. Bate , Joe J. Monaghan

During reionization, the intergalactic medium is heated impulsively by supersonic ionization fronts (I-fronts). The peak gas temperatures behind the I-fronts, $T_\mathrm{reion}$, are a key uncertainty in models of the thermal history after…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-10 Anson D'Aloisio , Matthew McQuinn , Oliver Maupin , Frederick B. Davies , Hy Trac , Spencer Fuller , Phoebe R. Upton Sanderbeck

We have modelled the process of reionization of the IGM by photoionization by galaxies, in order to predict the epoch of reionization. We use a sophisticated semi-analytic model to track the formation of galaxies. Our study represents a…

Astrophysics · Physics 2009-11-11 A. J. Benson , Naoshi Sugiyama , Adi Nusser , C. G. Lacey

The rigorous solution to the grating diffraction problem is a cornerstone step in many scientific fields and industrial applications ranging from the study of the fundamental properties of metasurfaces to the simulation of photolithography…

Computational Physics · Physics 2025-02-05 Evgeniy Levdik , Alexey A. Shcherbakov

The measurements of the 21-cm brightness temperature fluctuations from the neutral hydrogen at the Epoch of Reionization (EoR) should inaugurate the next generation of cosmological observables. In this respect, many works have concentrated…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-10 Sebastien Clesse , Laura Lopez-Honorez , Christophe Ringeval , Hiroyuki Tashiro , Michel H. G. Tytgat

We show that the algorithm based on the weighted essentially nonoscillatory (WENO) scheme with anti-diffusive flux corrections can be used as a solver of the radiative transfer equations. This algorithm is highly stable and robust for…

Astrophysics · Physics 2009-11-11 Jing-Mei Qiu , Chi-Wang Shu , Long-Long Feng , Li-Zhi Fang

The cross sections for single-electron photo-ionisation in two-electron atoms show fluctuations which decrease in amplitude when approaching the double-ionisation threshold. Based on semiclassical closed orbit theory, we show that the…

Atomic Physics · Physics 2009-11-13 Chang Woo Byun , Nark Nyul Choi , Min-Ho Lee , Gregor Tanner

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

In the framework of a two-moment photo-hydrodynamic modelling of radiation transport, we introduce a concept for the determination of effective radiation transport coefficients based on the minimization of the local entropy production rate…

Statistical Mechanics · Physics 2014-11-18 Thomas Christen , Frank Kassubek

Predictions for the ability of 21-cm interferometric experiments to discriminate Epoch of Reionization (EoR) signal models are typically limited by the simplicity of data models, whereby foreground signals and characteristics of the…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-29 Ainulnabilah Nasirudin , Steven Murray , Cathryn Trott , Bradley Greig , Ronniy Joseph , Chris Power

We study photon scattering errors in stimulated Raman driven quantum logic gates. For certain parameter regimes, we find that previous, simplified models of the process significantly overestimate the gate error rate due to photon…

We present a quantitative model for magneto-optical traps operating on narrow transitions, where the transition linewidth and the recoil shift are comparable. We combine a quantum treatment of the light scattering process with a Monte-Carlo…

Large fluctuations in the electron column density can occur during the reionization process. We investigate the possibility of deriving the electron density fluctuations through detailed mapping of the redshifted 21-cm emission from the…

Astrophysics · Physics 2009-11-11 Gilbert Holder , Ilian T. Iliev , Garrelt Mellema

We examine the temperature structure of the IGM due to the passage of individual ionisation fronts using a radiative transfer (RT) code coupled to a particle-mesh (PM) N-body code. Multiple simulations were performed with different spectra…

Astrophysics · Physics 2009-11-11 Eric R. Tittley , Avery Meiksin

The observed 21-cm signal from the epoch of reionization will be distorted along the line-of-sight by the peculiar velocities of matter particles. These redshift-space distortions will affect the contrast in the signal and will also make it…

We discuss imaging sources from low relative-velocity correlations in heavy-ion reactions. When the correlation is dominated by interference, we can obtain the images by Fourier transforming the correlation function. In the general case, we…

Nuclear Theory · Physics 2007-05-23 P. Danielewicz , D. A. Brown

Known populations of QSOs appear to fall short of producing the ionizing flux required for re-ionizing the universe. The alternative, galaxies as sources of ionizing photons, suffers from the problem that known types of galaxies are almost…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Michael Rauch
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