NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-04-18 T15:04:28 PDT
Help | Comment | NED Home

For refcode 2014AJ....148...65O:
Retrieve 10 NED objects in this reference.
Please click here for ADS abstract

NED Abstract

Copyright by American Astronomical Society. Reproduced by permission
2014AJ....148...65O A Magnified View of Star Formation at z = 0.9 From Two Lensed Galaxies Olmstead, Alice; Rigby, Jane R.; Swinbank, Mark; Veilleux, Sylvain Abstract. We present new narrowband Halpha imaging from the Hubble Space Telescope of two z = 0.91 galaxies that have been lensed by the foreground galaxy cluster A2390. These data probe spatial scales as small as ~0.3 kpc, providing a magnified look at the morphology of star formation at an epoch when the global star formation rate (SFR) was high. However, dust attenuates our spatially resolved SFR indicators, the Halpha and rest-UV emission, and we lack a direct measurement of extinction. Other studies have found that ionized gas in galaxies tends to be roughly 50% more obscured than stars; however, given an unextincted measurement of the SFR we can quantify the relative stellar to nebular extinction and the extinction in Halpha. We infer SFRs from Spitzer and Herschel mid- to far-infrared observations and compare these to integrated Halpha and rest-UV SFRs; this yields stellar to nebular extinction ratios consistent with previous studies. We take advantage of high spatial resolution and contextualize these results in terms of the source-plane morphologies, comparing the distribution of Halpha to that of the rest-frame UV and optical light. In one galaxy, we measure separate SFRs in visually distinct clumps, but can set only a lower limit on the extinction and thus the star formation. Consequently, the data are also consistent with there being an equal amount of extinction along the lines of sight to the ionized gas as to the stars. Future observations in the far-infrared could settle this by mapping out the dust directly. Based on new and archival observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. New observations are associated with program # 11678. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA. Key words: dust, extinction, galaxies: high-redshift, galaxies: star formation, gravitational lensing: strong
Retrieve 10 NED objects in this reference.
Please click here for ADS abstract

Back to NED Home