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Using a sample of dwarf irregular galaxies selected from the ALFALFA blind HI-survey and observed using the VIMOS IFU, we investigate the relationship between H$alpha$ emission and Balmer optical depth ($tau_{text{b}}$). We find a positive correlation between H$alpha$ luminosity surface density and Balmer optical depth in 8 of 11 at $geq$ 0.8$sigma$ significance (6 of 11 at $geq$ 1.0$sigma$) galaxies. Our spaxels have physical scales ranging from 30 to 80 pc, demonstrating that the correlation between these two variables continues to hold down to spatial scales as low as 30 pc. Using the Spearmans rank correlation coefficient to test for correlation between $Sigma_{text{H}alpha}$ and $tau_{text{b}}$ in all the galaxies combined, we find $rho = 0.39$, indicating a positive correlation at 4$sigma$ significance. Our low stellar-mass galaxy results are in agreement with observations of emission line regions in larger spiral galaxies, indicating that this relationship is independent of the size of the galaxy hosting the emission line region. The positive correlation between H$alpha$ luminosity and Balmer optical depth within spaxels is consistent with the hypothesis that young star-forming regions are surrounded by dusty birth-clouds.
Lyman-alpha emitters are thought to be young, low-mass galaxies with ages of ~10^8 yr. An overdensity of them in one region of the sky (the SSA 22 field) traces out a filamentary structure in the early Universe at a redshift of z = 3.1 (equivalent to
We present the results of the spectroscopic and photometric follow-up of two field galaxies that were selected as possible stellar counterparts of local high velocity clouds. Our analysis shows that the two systems are distant (D>20 Mpc) dwarf irregu
Turbulence has the potential for creating gas density enhancements that initiate cloud and star formation (SF), and it can be generated locally by SF. To study the connection between turbulence and SF, we looked for relationships between SF traced by
The near and mid-infrared characteristics of large amplitude, Mira, variables in Local Group dwarf irregular galaxies (LMC, NGC 6822, IC 1613, Sgr dIG) are described. Two aspects of these variables are discussed. First, the short period (P < 420 days
We use time-domain optical spectroscopy to distinguish between broad emission lines powered by accreting black holes (BHs) or stellar processes (i.e., supernovae) for 16 galaxies identified as AGN candidates by Reines etal (2013). Our study is primar