The Importance Of Star Formation Intensity In LY{\alpha} Escape From
  Green Pea Galaxies And Lyman Break Galaxy Analogs
  We have studied ultraviolet images of 40 Green Pea galaxies and 15 local
Lyman Break Galaxy Analogs to understand the relation between Ly$\alpha$ photon
escape and central UV photometric properties. We measured star formation
intensity (SFI, star formation rate per unit area) from the central 250 pc
region ($S_{\rm 250pc}$) using COS/NUV images from the \textit{Hubble Space
Telescope}. The measured $S_{\rm 250pc}$ of our sample Green Peas ranges from
2.3--46 $M_{\odot} \ \rm{year}^{-1} \ \rm{kpc^{-2}}$, with a geometric mean of
$15 M_{\odot} \ \rm{year}^{-1} \ \rm{kpc^{-2}}$ and a standard deviation of
0.266 dex, forming a relatively narrow distribution. The Lyman Break Galaxy
Analogs show a similarly narrow distribution of $S_{\rm 250pc}$ (0.271 dex),
though with a larger mean of 28 $M_{\odot} \ \rm{year}^{-1} \ \rm{kpc^{-2}}$.
We show that while the Ly$\alpha$ equivalent width (EW(Ly$\alpha$)) and the
Ly$\alpha$ escape fraction ($f^{Ly\alpha}_{esc}$) are not significantly
correlated with the central SFI ($S_{\rm 250pc}$), both are positively
correlated with the ratio of surface brightness to galaxy stellar mass ($S_{\rm
250pc}/M_{\rm star}$), with correlation coefficients ($p$-values) of 0.702
($1\times 10^{-8}$) and 0.529 ($5\times 10^{-4}$) with EW(Ly$\alpha$) and
$f^{Ly\alpha}_{esc}$, respectively. These correlations suggest a scenario where
intense central star formation can drive a galactic wind in galaxies with
relatively shallow gravitational potential wells, thus clearing channels for
the escape of Ly$\alpha$ photons.
