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Title: A new technique to isolate kinematically anomalous gas in HI data cubes
HI line observations of nearby galaxies often reveal the presence of extraplanar and/or kinematically anomalous gas that deviates from the general circular flow. In this work, we study the dependence of kinematically anomalous HI gas in galaxies taken from the SIMBA cosmological simulation on galaxy properties such as HI mass fraction, specific star formation rate, and local environmental density. To identify kinematically anomalous gas, we use a simple yet effective decomposition method to separate it from regularly rotating gas in the galactic disc; this method is well-suited for application to observational data sets but has been validated here using the simulation. We find that at fixed atomic gas mass fraction, the anomalous gas fraction increases with the specific star formation rate. We also find that the anomalous gas fraction does not have a significant dependence on a galaxy’s environment. Our decomposition method has the potential to yield useful insights from future HI surveys.  more » « less
Award ID(s):
1814421
PAR ID:
10481853
Author(s) / Creator(s):
; ;
Publisher / Repository:
Oxford University Press
Date Published:
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
518
Issue:
4
ISSN:
0035-8711
Page Range / eLocation ID:
5942 to 5952
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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