The MOSDEF-LRIS survey: detection of inflowing gas towards three star-forming galaxies at z ∼ 2

Authors

Andrew Weldon, University of California, RiversideFollow
Naveen Reddy, University of California - RiversideFollow
Michael W. Topping, University of Arizona
Alice E. Shapley, University of California - Los AngelesFollow
Xinnan Du, Stanford University
Sedona H. Price, University of Pittsburgh
Ryan L. Sanders, University of California, DavisFollow
Alison L. Coil, University of California - San Diego
Bahram Mobasher, University of California - Riverside
Mariska Kriek, Leiden University
Brian Siana, University of California, Riverside
Saeed Rezaee, University of California, Riverside

Abstract

We report on the discovery of cool gas inflows towards three star-forming galaxies at ∼ 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 (Σ_SFR). 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.

Document Type

Article

Publication Date

2023

Notes/Citation Information

© 2023 The Author(s)

Published by Oxford University Press on behalf of Royal Astronomical Society

Digital Object Identifier (DOI)

https://doi.org/10.1093/mnras/stad1615

Funding Information

We thank the anonymous referee for providing constructive feedback that improved the paper. We acknowledge support from NSF AAG grants AST1312780, 1312547, 1312764, and 1313171, grant AR13907 from the Space Telescope Science Institute, and grant NNX16AF54G from the NASA ADAP program. We thank the 3D-HST Collaboration, which provided the spectroscopic and photometric catalogues used to select the MOSDEF targets and derive stellar population parameters. This research made use of ASTROPY,6 a community-developed core PYTHON package for astronomy (Astropy Collaboration 2013, 2018). We wish to extend special thanks to those of Hawaiian ancestry on whose sacred mountain we are privileged to be guests. Without their generous hospitality, most of the observations presented herein would not have been possible.

Repository Citation

Weldon, Andrew; Reddy, Naveen; Topping, Michael W.; Shapley, Alice E.; Du, Xinnan; Price, Sedona H.; Sanders, Ryan L.; Coil, Alison L.; Mobasher, Bahram; Kriek, Mariska; Siana, Brian; and Rezaee, Saeed, "The MOSDEF-LRIS survey: detection of inflowing gas towards three star-forming galaxies at z ∼ 2" (2023). Physics and Astronomy Faculty Publications. 706.
https://uknowledge.uky.edu/physastron_facpub/706