Long troughs in the Lyman-α forest below redshift 6 due to islands of neutral hydrogen


Type
Article
Change log
Authors
Keating, LC 
Weinberger, LH 
Kulkarni, G 
Haehnelt, MG 
Chardin, J 
Abstract

A long (110 cMpc/h) and deep absorption trough in the Lyα forest has been observed extending down to redshift 5.5 in the spectrum of ULAS J0148+0600. Although no Lyα transmission is detected, Lyβ spikes are present which has led to claims that the gas along this trough must be ionized. Using high resolution cosmological radiative transfer simulations in large volumes, we show that in a scenario where reionization ends late (z∼5.2), our simulations can reproduce troughs as long as observed. In this model, we find that the troughs are caused by islands of neutral hydrogen. Small ionized holes within the neutral islands allow for the transmission of Lyβ. We have also modelled the Lyα emitter population around the simulated troughs, and show that there is a deficit of Lyα emitters close to the trough as is observed.

Description
Keywords
methods: numerical, galaxies: high-redshift, intergalactic medium, quasars: absorption lines, dark ages, reionization, first stars
Journal Title
Monthly Notices of the Royal Astronomical Society
Conference Name
Journal ISSN
0035-8711
1365-2966
Volume Title
491
Publisher
Oxford University Press (OUP)
Rights
Publisher's own licence
Sponsorship
European Research Council (320596)
Engineering and Physical Sciences Research Council (EP/P020259/1)
Science and Technology Facilities Council (ST/M007065/1)
STFC (ST/M007073/1)
Science and Technology Facilities Council (ST/R00689X/1)
STFC (ST/T001550/1)
Science and Technology Facilities Council (ST/N000927/1)
Science and Technology Facilities Council (1791046)
Science and Technology Facilities Council (ST/S000623/1)
Science and Technology Facilities Council (ST/J005673/1)
Science and Technology Facilities Council (ST/K00333X/1)
Science and Technology Facilities Council (ST/L000636/1)
Science and Technology Facilities Council (ST/P000673/1)
STFC (ST/T00049X/1)