Bibcode
Hattab, M. W.; de Souza, R. S.; Ciardi, B.; Paardekooper, J.-P.; Khochfar, S.; Dalla Vecchia, C.
Bibliographical reference
Monthly Notices of the Royal Astronomical Society, Volume 483, Issue 3, p.3307-3321
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3
2019
Citations
6
Refereed citations
6
Description
The dark ages of the Universe end with the formation of the first
generation of stars residing in primeval galaxies. These objects were
the first to produce ultraviolet ionizing photons in a period when the
cosmic gas changed from a neutral state to an ionized one, known as
Epoch of Reionization (EoR). A pivotal aspect to comprehend the EoR is
to probe the intertwined relationship between the fraction of ionizing
photons capable to escape dark haloes, also known as the escape fraction
(fesc), and the physical properties of the galaxy. This work
develops a sound statistical model suitable to account for such
non-linear relationships and the non-Gaussian nature of fesc.
This model simultaneously estimates the probability that a given
primordial galaxy starts the ionizing photon production and estimates
the mean level of the fesc once it is triggered. The model
was employed in the First Billion Years simulation suite, from which we
show that the baryonic fraction and the rate of ionizing photons appear
to have a larger impact on fesc than previously thought. A
naive univariate analysis of the same problem would suggest smaller
effects for these properties and a much larger impact for the specific
star formation rate, which is lessened after accounting for other galaxy
properties and non-linearities in the statistical model. A snippet code
to reproduce the analysis of this paper is available at COIN toolbox
Related projects
Numerical Astrophysics: Galaxy Formation and Evolution
How galaxies formed and evolved through cosmic time is one of the key questions of modern astronomy and astrophysics. Cosmological time- and length-scales are so large that the evolution of individual galaxies cannot be directly observed. Only through numerical simulations can one follow the emergence of cosmic structures within the current
Claudio
Dalla Vecchia