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We present a method to characterize star-formation driven outflows from edge-on galaxies and apply this method to the metal-poor starburst galaxy, Mrk 1486. Our method uses the distribution of emission line flux (from H β and [O iii] 5007) to identify the location of the outflow and measure the extent above the disc, the opening angle, and the transverse kinematics. We show that this simple technique recovers a similar distribution of the outflow without requiring complex modelling of line-splitting or multi-Gaussian components, and is therefore applicable to lower spectral resolution data. In Mrk 1486 we observe an asymmetric outflow in both the location of the peak flux and total flux from each lobe. We estimate an opening angle of 17–37° depending on the method and assumptions adopted. Within the minor axis outflows, we estimate a total mass outflow rate of ∼2.5 M⊙ yr−1, which corresponds to a mass loading factor of η = 0.7. We observe a non-negligible amount of flux from ionized gas outflowing along the edge of the disc (perpendicular to the biconical components), with a mass outflow rate ∼0.9 M⊙ yr−1. Our results are intended to demonstrate a method that can be applied to high-throughput low spectral resolution observations, such as narrow-band filters or low spectral resolution integral field spectrographs that may be more able to recover the faint emission from outflows.

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 (${\dot{\mathrm{\Sigma }}}_{\mathrm{out}}$) and star formation rate surface density (Σ_SFR),${\dot{\mathrm{\Sigma }}}_{\mathrm{out}}\propto {\mathrm{\Sigma }}_{\mathrm{SFR}}^{1.06\pm 0.10}$, and a strong correlation between${\dot{\mathrm{\Sigma }}}_{\mathrm{out}}$and the gas depletion time, such that${\dot{\mathrm{\Sigma }}}_{\mathrm{out}}\propto t_{\mathrm{dep}}^{-1.1\pm 0.06}$. 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 Σ_SFRin 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.

We study star formation-driven outflows in a z ∼ 0.02 starbursting disc galaxy, IRAS08339+6517, using spatially resolved measurements from the Keck Cosmic Web Imager (KCWI). We develop a new method incorporating a multistep process to determine whether an outflow should be fit in each spaxel, and then subsequently decompose the emission line into multiple components. We detect outflows ranging in velocity, vout, from 100 to 600 km s−1 across a range of star formation rate surface densities, ΣSFR, from ∼0.01 to 10 M⊙ yr−1 kpc−2 in resolution elements of a few hundred parsec. Outflows are detected in ∼100 per cent of all spaxels within the half-light radius, and ∼70 per cent within r90, suggestive of a high covering fraction for this starbursting disc galaxy. Around 2/3 of the total outflowing mass originates from the star forming ring, which corresponds to ${\lt}10{{\ \rm per\ cent}}$ of the total area of the galaxy. We find that the relationship between vout and the ΣSFR, as well as between the mass loading factor, η, and the ΣSFR, are consistent with trends expected from energy-driven feedback models. We study the resolution effects on this relationship and find stronger correlations above a re-binned size-scale of ∼500 pc. Conversely, we do not find statistically significant consistency with the prediction from momentum-driven winds.