Spatially Resolving Highly Ionized Channels of Lyman Continuum and Lyman Alpha Escape on 10's of Parsecs Scales In A Strongly Lensed Galaxy

Our understanding of the EOR will be limited by our ability to directly study the physical mechanisms that regulate LyC escape in galaxies where LyC escape can be directly measured. However, revealing the physics of LyC requires resolving the relevant physical scales, which are increasingly believed to be small, i.e. on the order of the size of individual compact star clusters (~10-100 pc). This work can only be performed with detailed studies of bright, highly magnified LyC leaking systems, but currently there is only one such system known (the Sunburst Arc). We propose UV/blue HST imaging of LyC and LyA of SGAS1110, an exceptionally magnified strongly lensed galaxy at z=2.48. The proposed data will spatially resolve escaping LyC and LyA radiation down to ~30 pc scales, identifying channels of extremely low HI column density. The target galaxy has a double-peaked LyA emission profile observed from galaxy-integrated ground-based spectroscopy, as well as JWST/NIRSpec IFU spectroscopy that identifies multiple compact star forming regions with extreme ionization (O3/O2 >11 and Ne3/O2 > 1.5; implying log(U) of ~ -1). These regions have nearly identical properties to the extreme LyC leaking region in the Sunburst Arc, which is associated with a single compact star cluster, ~<10 pc in size. This program would provide the crucial missing piece (direct imaging of spatially resolved LyC and LyA escape) to use SGAS1110 as a new laboratory for understanding the relationship between ionizing photon escape and spatially resolved physical properties on the physical scales of individual star clusters, as well as role that complex galaxy and ISM geometries play in enabling LyC escape.