Presentation #214.06 in the session Strong and Weak Gravitational Lensing.
It’s presumed that gas is ionized by extreme ultraviolet radiation and strong emission lines emerge in the presence of radiation from massive stars. The ultraviolet contains emission lines that can be used to constrain the properties of ionizing radiation within a galaxy. Using data taken from the MUSE spectrograph, we took a z=2.782 gravitationally lensed galaxy behind the cluster RCS2 032727-132623 and examined the strengths of the UV emission lines. We fit gaussian profiles to the individual lines: CIV 1548, 1551, OIII]1661, 1666, NIII] 1750, [SiIII]1883 + [SiIII]1892, and [CIII]1907 + CIII]1909. The presence of all of these lines is indicative of a strong ionizing radiation field. Using the flux ratios of these lines we determined whether the dominant source of ionizing radiation strongly lensed galaxy was star formation or an active galactic nucleus, and also measured line diagnostics that constrain the metallicity, electron density, and relative abundances of C, N and O in the galaxy. We then used the different abundance ratios to compare our lensed galaxy to local low red-shift dwarf starburst galaxies, which we found to have similar ratios.