English
Related papers

Related papers: The Escape Fraction of Ionizing Radiation from Gal…

200 papers

We model the escape of ionizing radiation from high-redshift galaxies using high-resolution Adaptive Mesh Refinement N-body + hydrodynamics simulations. Our simulations include time-dependent and spatially-resolved transfer of ionizing…

Astrophysics · Physics 2010-11-11 Nickolay Y. Gnedin , Andrey V. Kravtsov , Hsiao-Wen Chen

Low mass galaxies are thought to provide the bulk of the ionizing radiation necessary to reionize the Universe. The amount of photons escaping the galaxies is poorly constrained theoretically, and difficult to measure observationally. Yet…

Astrophysics of Galaxies · Physics 2017-05-03 Maxime Trebitsch , Jérémy Blaizot , Joakim Rosdahl , Julien Devriendt , Adrianne Slyz

It has been argued that low-luminosity dwarf galaxies are the dominant source of ionizing radiation during cosmological reionization. The fraction of ionizing radiation that escapes into the intergalactic medium from dwarf galaxies with…

Astrophysics · Physics 2011-02-11 John H. Wise , Renyue Cen

The escape fraction of ionizing photons from galaxies is a crucial quantity controlling the cosmic ionizing background radiation and the reionization. Various estimates of this parameter can be obtained in the redshift range, z=0--6, either…

Astrophysics · Physics 2009-11-11 Akio K. Inoue , Ikuru Iwata , Jean-Michel Deharveng

The part played by stars in the ionization of the intergalactic medium remains an open question. A key issue is the proportion of the stellar ionizing radiation that escapes the galaxies in which it is produced. Spectroscopy of gamma-ray…

Recent data indicates that the cosmic UV emissivity decreased with decreasing redshift z near the end of reionization. Lacking evidence for very massive early stars, this could signal a decline with time in the mass-averaged escape fraction…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 A. Ferrara , A. Loeb

Hydrogen in the Universe was (re)ionised between redshifts $z \approx 10$ and $z \approx 6$. The nature of the sources of the ionising radiation is hotly debated, with faint galaxies below current detection limits regarded as prime…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-17 Mahavir Sharma , Tom Theuns , Carlos S. Frenk , Richard G. Bower , Robert A. Crain , Matthieu Schaller , Joop Schaye

The UV escape fraction from high-redshift galaxies plays a key role in models of cosmic reionisation. Because it is currently not possible to deduce the escape fractions during the epoch of reionisation from observations, we have to rely on…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Jan-Pieter Paardekooper , Federico I. Pelupessy , Gabriel Altay , Chael Kruip

Using a suite of radiation hydrodynamic simulations of star cluster formation in turbulent clouds, we study the escape fraction of ionizing (Lyman continuum) and non-ionizing (FUV) radiation for a wide range of cloud masses and sizes. The…

Astrophysics of Galaxies · Physics 2019-10-02 Jeong-Gyu Kim , Woong-Tae Kim , Eve C. Ostriker

We use a three-dimensional radiation transfer code to calculate the steady-state escape fraction of ionizing photons from disk galaxies as a function of redshift and galaxy mass. The gaseous disks are assumed to be isothermal (with a sound…

Astrophysics · Physics 2009-10-31 Kenneth Wood , Abraham Loeb

The fraction of ionizing photons that escape their host galaxies to ionize hydrogen in the inter-galactic medium (IGM) is a critical parameter in analyses of the reionization era. In this paper we use the Meraxes semi-analytic galaxy…

Astrophysics of Galaxies · Physics 2023-12-11 Simon J. Mutch , Bradley Greig , Yuxiang Qin , Gregory B. Poole , J. Stuart B. Wyithe

Several observational and theoretical arguments suggest that starburst galaxies may rival quasars as sources of metagalactic ionizing radiation at redshifts z > 3. Reionization of the intergalactic medium (IGM) at z > 5 may arise, in part,…

Astrophysics · Physics 2009-10-31 Massimo Ricotti , J. Michael Shull

The Epoch of Reionization marks the last major phase transition in the early Universe, during which the majority of neutral hydrogen once filling the intergalactic medium was ionized by the first galaxies. The James Webb Space Telescope is…

Astrophysics of Galaxies · Physics 2025-07-01 Cody Carr , Renyue Cen , Sophia Flury , Sally Oey , Stephan McCandliss , Allison Strom

The fraction of ionizing photons which escape their host galaxy and so are able to ionize hydrogen in the inter-galactic medium (IGM) is a critical parameter in studies of the reionization era and early galaxy formation. In this paper we…

Astrophysics · Physics 2015-05-13 Jhan Srbinovsky , Stuart Wyithe

A fundamental requirement for reionizing the Universe is that a sufficient fraction of the ionizing photons emitted by galaxies successfully escapes into the intergalactic medium. However, due to the scarcity of high-redshift observational…

We investigate the properties of the galaxies that reionized the Universe and the history of cosmic reionization using the "Evolution and Assembly of GaLaxies and their environments" (EAGLE) cosmological hydrodynamical simulations. We…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-19 Mahavir Sharma , Tom Theuns , Carlos Frenk , Richard G. Bower , Robert A. Crain , Matthieu Schaller , Joop Schaye

The escape fraction, fesc, of ionizing photons from early galaxies is a crucial parameter for determining whether the observed galaxies at z > 6 are able to reionize the high-redshift intergalactic medium. Previous attempts to measure fesc…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-28 Elizabeth R. Fernandez , J. Michael Shull

The fraction of ionizing photons that escape high-redshift galaxies sensitively determines whether galaxies reionized the early universe. However, this escape fraction cannot be measured from high-redshift galaxies because the opacity of…

Astrophysics of Galaxies · Physics 2018-08-08 J. Chisholm , S. Gazagnes , D. Schaerer , A. Verhamme , J. R. Rigby , M. Bayliss , K. Sharon , M. Gladders , H. Dahle

Proto-galaxies forming in low-mass dark matter haloes are thought to provide the majority of ionizing photons needed to reionize the Universe, due to their high escape fractions of ionizing photons. We study how the escape fraction in…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-09 Jan-Pieter Paardekooper , Sadegh Khochfar , Claudio Dalla Vecchia

Newly formed stars have a profound impact on their environment by depositing energy and momentum into the surrounding gas. However, only a fraction of the stellar feedback is retained in the cloud and observational constraints are needed to…

‹ Prev 1 2 3 10 Next ›