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Understanding the interplay of stellar feedback and turbulence in the interstellar medium (ISM) is essential to modeling the evolution of galaxies. To determine the timescales over which stellar feedback drives turbulence in the ISM, we performed a spatially resolved, multi-wavelength study of the nearby star-forming dwarf galaxy UGC 4305 (aka Holmberg II). As indicators of turbulence on local scales (400 pc), we utilized ionized gas velocity dispersion derived from IFU H$\alpha$ observations and atomic gas velocity dispersion and energy surface densities derived from HI synthesis observations with the Very Large Array. These indicators of turbulence were tested against star formation histories over the past 560 Myr derived from Color-Magnitude Diagrams (CMD) using Spearman's rank correlation coefficient. The strongest correlation identified at the 400 pc scale is between measures of HI turbulence and star formation 70-140 Myr ago. We repeated our analysis of UGC 4305's current turbulence and past star formation activity on multiple physical scales ($\sim$560, and 800 pc) to determine if there are indications of changes in the correlation timescale with changes to the physical scale. No notable correlations were found at larger physical scales emphasizing the importance of analyzing star formation driven turbulence as a local phenomenon., Comment: 17 pages, 9 figure, accepted to AJ

Stellar feedback is fundamental to the modeling of galaxy evolution as it drives turbulence and outflows in galaxies. Understanding the timescales involved are critical for constraining the impact of stellar feedback on the interstellar medium (ISM). We analyzed the resolved star formation histories along with the spatial distribution and kinematics of the atomic and ionized gas of four nearby star-forming dwarf galaxies (NGC 4068, NGC 4163, NGC 6789, UGC 9128) to determine the timescales over which stellar feedback drives turbulence. The four galaxies are within 5 Mpc and have a range of properties including current star formation rates of 0.0005 to 0.01 M$_{\odot}$ yr$^{-1}$, log(M$_*$/M$_{\odot}$) between 7.2 and 8.2, and log(M$_{HI}$/M$_\odot$) between 7.2 and 8.3. Their Color-Magnitude Diagram (CMD) derived star formation histories over the past 500 Myrs were compared to their atomic and ionized gas velocity dispersion and HI energy surface densities as indicators of turbulence. The Spearman's rank correlation coefficient was used to identify any correlations between their current turbulence and their past star formation activity on local scales ($\sim$400 pc). The strongest correlation found was between the HI turbulence measures and the star formation rate 100-200 Myrs ago. This suggests a coupling between the star formation activity and atomic gas on this timescale. No strong correlation between the ionized gas velocity dispersion and the star formation activity between 5-500 Myrs ago was found. The sample and analysis are the foundation of a larger program aimed at understanding the timescales over which stellar feedback drives turbulence., Comment: 21 pages, 19 figures. Accepted for publication in AJ