The Effect of Bi-conical Outflows on Ly$\alpha$ Escape From Green Peas
  We analyze the spectra of $10$ Green Pea galaxies, previously studied by
Henry et al. (2015), using a semi-analytical line transfer (SALT) model to
interpret emission and absorption features observed in UV galactic spectra. We
focus our analysis on various ionization states of silicon, associated with the
cool ($\sim 10^4$ K) and warm ($\sim 10^5$ K) gas. By analyzing low-ionization
lines, we study the relationships between the distribution and kinematics of
the outflowing H I gas and the observed Ly$\alpha$ escape fraction,
$f_{esc}^{Ly\alpha}$, as well as the Ly$\alpha$ emission peak separation,
$\Delta_{peak}$. We find that outflow geometries which leave a portion of the
source uncovered along the line of sight create the best conditions for
Ly$\alpha$ escape and have narrow peak separations, while geometries which
block the observer's view of the source create the worst conditions for
Ly$\alpha$ escape and have large peak separations. To isolate the effects of
outflow kinematics, we restricted our testing set to galaxies with spherical
outflows and found that $f_{esc}^{Ly\alpha}$ and the Ly$\alpha$ luminosity both
increase with the extent of the galactic winds. A simple estimate suggests that
the collisional excitation of neutral hydrogen by free electrons in the cool
gas of the winds can account for the Ly$\alpha$ luminosity observed in these
objects. Finally, we speculate on the relationship between outflows and the
escape of ionizing radiation from the CGM.
