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Related papers: Relativistic Ionization Fronts

200 papers

We present a detailed analysis of the ionization and thermal structure of the intergalactic medium (IGM) around a high-redshift QSO using a large suite of cosmological, multi-frequency radiative transfer (RT) simulations, exploring the…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-18 Koki Kakiichi , Luca Graziani , Benedetta Ciardi , Avery Meiksin , Michele Compostella , Marius B. Eide , Saleem Zaroubi

A self-consistent relativistic two-fluid model is proposed for one-dimensional electron-ion plasma dynamics. A multiple scales perturbation technique is employed, leading to an evolution equation for the wave envelope, in the form of a…

Plasma Physics · Physics 2016-07-06 M. McKerr , F. Haas , I. Kourakis

The fate of ionizing radiation is vital for understanding cosmic ionization, energy budgets in the interstellar and intergalactic medium, and star formation rate indicators. The low observed escape fractions of ionizing radiation have not…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 D. J. Hanish , M. S. Oey , J. R. Rigby , D. F. de Mello , J. C. Lee

Observations of the epoch of reionization give us clues about the nature and evolution of the sources of ionizing photons, or early stars and galaxies. We present a new suite of structure formation and radiative transfer simulations from…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-27 Keri L. Dixon , Ilian T. Iliev , Garrelt Mellema , Kyungjin Ahn , Paul R. Shapiro

The history of the transition from a neutral intergalactic medium (IGM) to one that is almost fully ionized can reveal the character of cosmological ionizing sources. We study the evolution of the volume filling factor of HII and HeIII…

Astrophysics · Physics 2009-10-30 Piero Madau , Francesco Haardt , Martin J. Rees

We construct a simple but self-consistent analytic ionization model for rapid exploration of 21cm power spectrum observables in redshift space. It is fully described by the average ionization fraction $x_e(z)$ and HII patch size $R(z)$ and…

Astrophysics · Physics 2009-11-13 Xiaomin Wang , Wayne Hu

Motivated by recent evidence that the epoch of reionization of hydrogen may have ended at a redshift as low as z~6 we consider the detectability of the sources responsible for this reionization. The main idea is that reionization places…

Astrophysics · Physics 2009-11-10 M. Stiavelli , S. M. Fall , N. Panagia

We study the stochastic dynamics of c and b quarks, produced in hard initial processes, in the hot medium created after the collision of two relativistic heavy ions. This is done through the numerical solution of the relativistic Langevin…

High Energy Physics - Phenomenology · Physics 2015-05-19 W. M. Alberico , A. Beraudo , A. De Pace , A. Molinari , M. Monteno , M. Nardi , F. Prino

We explore streaming instabilities of the electron-ion plasma with relativistic and ultra-relativistic cosmic rays in the background magnetic field in the multi-fluid approach. Cosmic rays can be both electrons and ions. The drift speed of…

High Energy Astrophysical Phenomena · Physics 2015-06-11 A. K. Nekrasov

We consider a new variant of cosmological perturbation theory that has been designed specifically to include non-linear density contrasts on scales 100 Mpc, while still allowing for linear fluctuations on larger scales. This theory is used…

General Relativity and Quantum Cosmology · Physics 2019-04-08 Christopher S. Gallagher , Timothy Clifton

The non-resonant two-photon one-electron ionization of neutral atoms is studied theoretically in the framework of relativistic second-order perturbation theory and independent particle approximation. In particular, the importance of…

Atomic Physics · Physics 2016-12-14 Jiri Hofbrucker , Andrey V. Volotka , Stephan Fritzsche

An ionization front (I-front) that propagates through an inhomogeneous medium is slowed down by self-shielding and recombinations. We perform cosmological radiation hydrodynamics simulations of the I-front propagation during the epoch of…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-12 Tsang Keung Chan , Alejandro Benitez-Llambay , Tom Theuns , Carlos Frenk , Richard Bower

We review the broad band properties of X-ray detected hotspots in radio galaxies and quasars. We show that their collective properties can be unified in a framework involving frequency dependent relativistic beaming and varying orientations…

Astrophysics · Physics 2009-11-07 Markos Georganopoulos , Demosthenes Kazanas

The first, self-consistent calculations are presented of the cosmological, H2-dissociating UV background produced during the epoch of reionization by the sources of reionization. Large-scale radiative transfer simulations of reionization…

Astrophysics · Physics 2015-05-13 Kyungjin Ahn , Paul R. Shapiro , Ilian T. Iliev , Garrelt Mellema , Ue-Li Pen

Coupled radiative-hydrodynamics simulations of the epoch of reionization aim to reproduce the propagation of ionization fronts during the transition before the overlap of HII regions. Many of these simulations use moment-based methods to…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-13 Nicolas Deparis , Dominique Aubert , Pierre Ocvirk , Jonathan Chardin , Joseph Lewis

The expansion of ionization fronts in uniform and spherically symmetric power-law density distributions is a well-studied topic. However, in many situations, such as a star formed at the edge of a molecular cloud core, an offset power-law…

Astrophysics · Physics 2009-11-13 S. J. Arthur

We obtain an extension of Bjorken's 1+1 dimensional scaling relativistic flow solution to relativistic transverse velocities with cylindrical symmetry in 1+3 dimensions at constant, homogeneous pressure (vanishing sound velocity). This can…

Nuclear Theory · Physics 2009-10-31 Tamas S. Biro

We study quasar proximity zones in the redshift range $5.77 \leq z \leq 6.54$ by homogeneously analyzing $34$ medium resolution spectra, encompassing both archival and newly obtained data, and exploiting recently updated systemic redshift…

We study the inhomogeneous reionization in a critical density CDM universe due to stellar sources, including Population III objects. The spatial distribution of the sources is obtained from high resolution numerical N-body simulations. We…

Astrophysics · Physics 2009-10-31 B. Ciardi , A. Ferrara , F. Governato , A. Jenkins

The first detection of a diffuse radio source in a cluster of galaxies, dates back to the 1959 (Coma Cluster, Large et al. 1959). Since then, synchrotron radiating radio sources have been found in several clusters, and represent an…

High Energy Astrophysical Phenomena · Physics 2015-05-27 L. Feretti , G. Giovannini , F. Govoni , M. Murgia