The kinematics and geometric properties of the neutral ISM and CGM in star forming galaxies are crucial regulators of the radiative transfer and escape of both Lyman-alpha and Lyman-continuum radiation. Because the two kinds of radiation are affected differently by the gas, they can in turn provide complementary information about the gas. This realization has in recent years led to a host of publications about the links between observables and astrophysical properties of the neutral gas. Here, I will present a strongly gravitationally lensed star-forming galaxy at z=2.4 which has turned out to be a rather remarkable laboratory for understanding the interplay of star formation feedback, neutral gas kinematics, and Lyman radiation escape. Strong Lyman-continuum emission is leaking from a compact, unresolved region coincident with a strongly star-forming cluster complex, spatially separated from other clump complexes with no such ionizing emission, seen in high enough spatial resolution to obtain non-overlapping optical spectroscopy of these regions. The combination of rarely seen intrinsic properties and the strong magnification and multiple lensed images could potentially help break some long standing degeneracies in our picture of the neutral medium of early Starburst galaxies, with implications for both the EoR and Lyman-alpha cosmology.

Host: Matthew Bayliss