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Title: A Spectral Atlas of Lyα Emitters at z = 5.7 and z = 6.6
Abstract We present two uniformly observed spectroscopic samples of Lyαemitters (LAEs; 127 atz= 5.7 and 82 atz= 6.6), which we use to investigate the evolution of the LAE population at these redshifts. The observations cover a large field (44 deg2) in the North Ecliptic Pole, as well as several smaller fields. We have a small number of exotic LAEs in the samples: double-peaked Lyαprofiles; very extended red wings; and one impressive lensed LAE cross. We also find three broad-line active galactic nuclei. We compare the Lyαline width measurements at the two redshifts, finding that the lower-luminosity LAEs show a strong evolution of decreasing line width with increasing redshift, while the high-luminosity LAEs do not, with a transition luminosity of logL(Lyα) ≈ 43.25 erg s−1. Thus, atz= 6.6, the high-luminosity LAEs may be producing large ionized bubbles themselves, or they may be residing in overdense galaxy sites that are producing such bubbles. In order to avoid losses in the red wing, the radius of the ionized bubble must be larger than 1 pMpc. The double-peaked LAEs also require transmission on the blue side. For the four atz= 6.6, we use models to estimate the proximity radii,Ra, where the ionizing flux of the galaxy is sufficient to make the surroundings have a low enough neutral fraction to pass the blue light. Since the requiredRaare large, multiple ionizing sources in the vicinity may be needed.  more » « less
Award ID(s):
1716093
PAR ID:
10655848
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
IOP Science
Date Published:
Journal Name:
The Astrophysical Journal
Edition / Version:
1
Volume:
971
Issue:
2
ISSN:
0004-637X
Page Range / eLocation ID:
136
Subject(s) / Keyword(s):
Cosmological evolution Lyman-alpha galaxies Reionization
Format(s):
Medium: X Size: 1.3MB Other: PDF/A
Size(s):
1.3MB
Sponsoring Org:
National Science Foundation
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