Lyα Halos around [O iii]-selected Galaxies in HETDEX
Abstract

We present extended Lyαemission out to 800 kpc of 1034 [Oiii]-selected galaxies at redshifts 1.9 <z< 2.35 using the Hobby–Eberly Telescope Dark Energy Experiment. The locations and redshifts of the galaxies are taken from the 3D-HST survey. The median-stacked surface brightness profile of the Lyαemission of the [Oiii]-selected galaxies agrees well with that of 968 bright Lyα-emitting galaxies (LAEs) atr> 40 kpc from the galaxy centers. The surface brightness in the inner parts (r< 10 kpc) around the [Oiii]-selected galaxies, however, is 10 times fainter than that of the LAEs. Our results are consistent with the notion that photons dominating the outer regions of the Lyαhalos are not produced in the central galaxies but originate outside of them.

Authors:
; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publication Date:
NSF-PAR ID:
10369178
Journal Name:
The Astrophysical Journal Letters
Volume:
934
Issue:
2
Page Range or eLocation-ID:
Article No. L26
ISSN:
2041-8205
Publisher:
DOI PREFIX: 10.3847
National Science Foundation
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