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  • A SPectroscopic Survey of Biased Halos in the Reionization Era (ASPIRE): JWST Discovers an Overdensity around a Metal Absorption-selected Galaxy at z ∼ 5.5
Title: A SPectroscopic Survey of Biased Halos in the Reionization Era (ASPIRE): JWST Discovers an Overdensity around a Metal Absorption-selected Galaxy at z ∼ 5.5
Abstract The launch of JWST opens a new window for studying the connection between metal-line absorbers and galaxies at the end of the Epoch of Reionization. Previous studies have detected absorber–galaxy pairs in limited quantities through ground-based observations. To enhance our understanding of the relationship between absorbers and their host galaxies atz> 5, we utilized the NIRCam wide-field slitless spectroscopy to search for absorber-associated galaxies by detecting their rest-frame optical emission lines (e.g., [OIII] + Hβ). We report the discovery of a Mgii-associated galaxy atz= 5.428 using data from the JWST ASPIRE program. The Mgiiabsorber is detected on the spectrum of quasar J0305–3150 with a rest-frame equivalent width of 0.74 Å. The associated galaxy has an [OIII] luminosity of 1042.5erg s−1with an impact parameter of 24.9 pkpc. The joint Hubble Space Telescope–JWST spectral energy distribution (SED) implies a stellar mass and star formation rate ofM*≈ 108.8M⊙, star-formation rate  ≈ 10M⊙yr−1. Its [OIII] equivalent width and stellar mass are typical of [OIII] emitters at this redshift. Furthermore, connecting the outflow starting time to the SED-derived stellar age, the outflow velocity of this galaxy is ∼300 km s−1, consistent with theoretical expectations. We identified six additional [OIII] emitters with impact parameters of up to ∼300 pkpc at similar redshifts (∣dv∣ < 1000 km s−1). The observed number is consistent with that in cosmological simulations. This pilot study suggests that systematically investigating the absorber–galaxy connection within the ASPIRE program will provide insights into the metal-enrichment history in the early Universe.  more » « less
Award ID(s):
2308258 1751404
PAR ID:
10520633
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; ; ; ; ; ; ; ; ; « less
Publisher / Repository:
IOP
Date Published:
Journal Name:
The Astrophysical Journal Letters
Volume:
956
Issue:
2
ISSN:
2041-8205
Page Range / eLocation ID:
L40
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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