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Title: The MOSDEF-LRIS survey: detection of inflowing gas towards three star-forming galaxies at z ∼ 2
ABSTRACT We report on the discovery of cool gas inflows towards three star-forming galaxies at <z> ∼ 2.30. Analysis of Keck Low-Resolution Imaging Spectrometer spectroscopy reveals redshifted low-ionization interstellar (LIS) metal absorption lines with centroid velocities of 60–130 km s−1. These inflows represent some of the most robust detections of inflowing gas into isolated, star-forming galaxies at high redshift. Our analysis suggests that the inflows are due to recycling metal-enriched gas from previous ejections. Comparisons between the galaxies with inflows and a larger parent sample of 131 objects indicate that galaxies with detected inflows may have higher specific star formation rates (sSFRs) and star-formation-rate surface densities (ΣSFR). However, when additional galaxies without robustly detected inflows based on centroid velocity but whose LIS absorption line profiles indicate large red-wing velocities are considered, galaxies with inflows do not show unique properties relative to those lacking inflows. Additionally, we calculate the covering fraction of cool inflowing gas as a function of red-wing inflow velocity, finding an enhancement in high-sSFR binned galaxies, likely due to an increase in the amount of recycling gas. Together, these results suggest that the low detection rate of galaxies with cool inflows is primarily related to the viewing angle rather than the physical properties of the galaxies.  more » « less
Award ID(s):
2009313
PAR ID:
10427778
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
523
Issue:
4
ISSN:
0035-8711
Page Range / eLocation ID:
5624 to 5634
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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