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Escape fraction of ionizing photons from galaxies at z=0--6

Akio K. Inoue·Ikuru Iwata·Jean-Michel Deharveng
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Abstract

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 from direct observations or from the observed ionizing background intensities. We compare them homogeneously in terms of the observed flux density ratio of ionizing ($\sim900$ Årest-frame) to non-ionizing ultraviolet ($\sim1500$ Årest-frame) corrected for the intergalactic absorption. The escape fraction is found to increase by an order of magnitude, from a value less than 0.01 at $z\la1$ to about 0.1 at $z\ga4$.

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Akio K. Inoue, Ikuru Iwata, Jean-Michel Deharveng. 2006-05-20. Escape fraction of ionizing photons from galaxies at z=0--6. https://doi.org/10.1111/j.1745-3933.2006.00195.x

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