A magnified view of star formation at z = 0.9 from two lensed galaxies

摘要: We present new narrowband Hα imaging from the Hubble Space Telescope of two z = 0.91 galaxies that have been lensed by foreground galaxy cluster A2390. These data probe spatial scales as small ∼0.3 kpc, providing a magnified look at morphology star formation an epoch when global rate (SFR) was high. However, dust attenuates our spatially resolved SFR indicators, and rest-UV emission, we lack direct measurement extinction. Other studies found ionized gas in tends to be roughly 50% more obscured than stars; however, given unextincted can quantify relative stellar nebular extinction Hα. infer SFRs Spitzer Herschel mid- far-infrared observations compare these integrated SFRs; this yields ratios consistent with previous studies. take advantage high resolution contextualize results terms source-plane morphologies, comparing distribution rest-frame UV optical light. In one galaxy, measure separate visually distinct clumps, but set only lower limitmore » on thus formation. Consequently, are also there being equal amount along lines sight stars. Future could settle mapping out directly.« less