Neutral Gas Properties and Ly$\alpha$ Escape in Extreme Green Pea Galaxies

Understand

Mechanisms regulating the escape of Ly$\alpha$ photons and ionizing radiation remain poorly understood.

• To study these processes we analyze VLA 21cm observations of one Green Pea (GP), J160810+352809 (hereafter J1608), and HST COS spectra of 17 GP galaxies at $z<0.2$.
• All are highly ionized: J1608 has the highest [O III] $\lambda5007$/[O II] $\lambda3727$ for star-forming galaxies in SDSS, and the 17 GPs have [O III]/[O II] $\geq6.6$.
• We set an upper limit on J1608's HI mass of $\log M_{HI}/M_\odot=8.4$, near or below average compared to similar mass dwarf galaxies.