J/MNRAS/517/3263 IGM Neutral Fraction Inference (Bolan+, 2022)
Inferring the intergalactic medium neutral fraction at z ∼ 6-8 with
low-luminosity Lyman break galaxies.
Bolan P., Lemaux B.C., Mason C., Bradac M., Treu T., Strait V.,
Pelliccia D., Pentericci L., Malkan M.
<Mon. Not. R. Astron. Soc. 517, 3263-3274 (2022)>
=2022MNRAS.517.3263B 2022MNRAS.517.3263B (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies ; Photometry, ultraviolet
Keywords: galaxies: evolution - galaxies: high-redshift - intergalactic medium -
galaxies: ISM, dark ages, reionization, first stars
Abstract:
We present a Bayesian inference on the neutral hydrogen fraction of
the intergalactic medium (IGM), {bar}xhi, at z∼6-8 using the
properties of Lyman break galaxies during the Epoch of Reionization.We
use large samples of LBG candidates at 5.5≤z≤8.2 with spectroscopy
from Keck/DEIMOS and Keck/MOSFIRE. For each galaxy, we incorporate
either the Lyman-α equivalent width (EW) for detections or the
EW limit spectrum for nondetections to parameterize the EW
distribution at various ultraviolet brightnesses for a given redshift.
Using our reference sample of galaxy candidates from the ionized
universe at z∼6.0, we are able to infer {bar}xhi at two redshifts:
z∼6.7 and z∼7.6. This work includes intrinsically faint,
gravitationally lensed galaxies at z∼6.0 in order to constrain the
intrinsic faint-end Lyα EW distribution and provide a comparable
population of galaxies to counterparts in our sample that are at
higher redshift. The inclusion of faint galaxy candidates, in addition
to a more sophisticated modelling framework, allows us to better
isolate effects of the interstellar medium and circumgalactic medium
on the observed Lyman-α distribution from those of the IGM. We
infer an upper limit of {bar}xhi≤0.25 at z=6.7±0.2 and a neutral
fraction of {bar}xhi=0.83+0.08-0.11 at z=7.6±0.6, both within
1σ uncertainty, results which favor a moderately late and rapid
reionization.
Description:
This table contains information on the properties of LBGs without
spectroscopic Lyman-alpha from Keck/DEIMOS.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
nondet.dat 109 162 *Information on the properties of LBGs without
spectroscopic Lyman-alpha from Keck/DEIMOS
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Note on nondet.dat: Data describing the non-emitters from
Fuller et al. (2020ApJ...896..156F 2020ApJ...896..156F)
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Byte-by-byte Description of file: nondet.dat
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Bytes Format Units Label Explanations
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1- 8 I8 --- specID Spectroscopic ID from DEIMOS observations
10- 29 F20.16 deg RAdeg Right ascension (J2000)
31- 50 F20.16 deg DEdeg Declination (J2000)
52- 55 F4.1 mag mag F160W apparent magnitude (AB)
57- 60 F4.1 --- pznopri Peak value of the P(z) function
62- 66 F5.2 --- b_mu Lower 1 sigma limit on magnification
68- 73 F6.2 --- B_mu Upper 1 sigma limit on magnification
75- 79 F5.2 --- mu Magnification value
81- 85 F5.1 mag UVMAG Absolute UV magnitude
87- 92 F6.4 --- L/L* Luminosity with respect to characteristic
luminosity
94- 97 F4.2 --- Pz57 Fraction of integrated P(z) which falls
between the redshifts 5 and 7
99-103 F5.2 --- beta UV beta slope
105-109 F5.1 --- EWlim 1 sigma equivalent width limit on Lyman-alpha
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Acknowledgements:
Patricia Bolan, pmbolan(at)ucdavis.edu
References:
Hoag et al., 2019ApJ...878...12H 2019ApJ...878...12H
(End) Patricia Vannier [CDS] 12-May-2022