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Description
Exploiting the slitless spectroscopy taken as part of the Grism Lens-Amplified Survey from Space (GLASS), we present an extended analysis of the spatial distribution of star formation in 76 galaxies in 10 clusters at 0.3<z<0.7. We use 85 foreground and background galaxies in the same redshift range as a field sample. The samples are well matched in stellar mass (10^8^-10^11^M_{sun}_) and star formation rate (0.5-50M_{sun}_/yr). We visually classify galaxies in terms of broad band morphology, H{alpha} morphology, and likely physical process acting on the galaxy. Most H{alpha} emitters have a spiral morphology (41%+/-8% in clusters, 51%+/-8% in the field), followed by mergers/interactions (28%+/-8%, 31%+/-7%, respectively) and early-type galaxies (remarkably as high as 29%+/-8% in clusters and 15%+/-6% in the field). A diversity of H{alpha} morphologies is detected, suggesting a diversity of physical processes. In clusters, 30%+/-8% of the galaxies present a regular morphology, mostly consistent with star formation diffused uniformly across the stellar population (mostly in the disk component, when present). The second most common morphology (28%+/-8%) is asymmetric/jellyfish, consistent with ram-pressure stripping or other non-gravitational processes in 18%+/-8% of the cases. Ram-pressure stripping appears significantly less prominent in the field (2%+/-2%), where the most common morphology/mechanism appears to be consistent with minor gas-rich mergers or clump accretion. This work demonstrates that while environment-specific mechanisms affect galaxy evolution at this redshift, they are diverse and their effects are subtle. A full understanding of this complexity requires larger samples and detailed and spatially resolved physical models.
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