Spatial Variation in Strong Line Ratios and Physical Conditions in Two Strongly Lensed Galaxies at z ∼ 1.4

For studies of galaxy formation and evolution, one the major benefits James Webb Space Telescope is that space-based IFUs like those on its NIRSpec MIRI instruments will enable spatially resolved spectroscopy distant galaxies, including at scale individual star-forming regions in galaxies have been gravitationally lensed. In meantime, there only a very small subset lensed sources where work this possible even with Hubble Telescope's Wide Field Camera 3 infrared channel grisms. We examine two these sources, SDSS J1723+3411 J2340+2947, using HST WFC3/IR grism data supporting spatially-unresolved from several ground-based to explore size spatial variations observed strong emission line ratios O32, R23, which are sensitive ionization parameter metallicity, Balmer decrement as an indicator reddening. find significant variation reddening reddening-corrected O32 R23 values correspond spreads few tenths dex metallicity. also clear evidence negative radial gradient star J2340+2947 tentative J1723+3411, though quite asymmetric. Finally, we can vary enough make spatially-resolved corrections necessary order characterize gradients physical conditions inferred them, necessitating use for future larger, more statistically robust samples.