DUVET: Spatially Resolved Observations of Star Formation Regulation via Galactic Outflows in a Starbursting Disk Galaxy
Abstract

We compare 500 pc scale, resolved observations of ionized and molecular gas for thez∼ 0.02 starbursting disk galaxy IRAS08339+6517, using measurements from KCWI and NOEMA. We explore the relationship of the star-formation-driven ionized gas outflows with colocated galaxy properties. We find a roughly linear relationship between the outflow mass flux ($Σ̇out$) and star formation rate surface density (ΣSFR),$Σ̇out∝ΣSFR1.06±0.10$, and a strong correlation between$Σ̇out$and the gas depletion time, such that$Σ̇out∝tdep−1.1±0.06$. Moreover, we find these outflows are so-calledbreakoutoutflows, according to the relationship between the gas fraction and disk kinematics. Assuming that ionized outflow mass scales with total outflow mass, our observations suggest that the regions of highest ΣSFRin IRAS08 are removing more gas via the outflow than through the conversion of gas into stars. Our results are consistent with a picture in which the outflow limits the ability of a region of a disk to maintain short depletion times. Our results underline the need for resolved observations of outflows in more galaxies.

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Publication Date:
NSF-PAR ID:
10386746
Journal Name:
The Astrophysical Journal
Volume:
941
Issue:
2
Page Range or eLocation-ID:
Article No. 163
ISSN:
0004-637X
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DOI PREFIX: 10.3847
National Science Foundation
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