Spectroscopic Analysis of Local Analogs
Abstract
The cause and progression of the reionization of the universe remain a mystery in cosmology today. Assuming star-forming galaxies were the dominant source of the ionizing photons needed to initiate and maintain reionization, we must then understand the number of contributing galax- ies, their ionizing radiation production, and how much of their ionizing radiation is able to escape. However, studying the production of ionizing radiation and its escape from galaxies during this period is challenging because the ionizing radiation is absorbed by neutral hydrogen in the interstellar and intergalactic media. Thus, we turn to galaxies in the lo- cal universe, studying six galaxies between z = 0.01-0.05. Using high S/N spectra collected from Magellan/LDSS3 and LBT/MODS, we measure the intensity of emission lines and perform line ratio analysis to explore the properties of these galaxies. In this work presents our preliminary anal- ysis of the emission line fluxes, line ratios and equivalent widths of the galaxies. Focusing on the [OIII]/[OII] and He I line ratios, we compare the six galaxies with samples known to be leaking Lyman continuum (LyC) radiation and find that they exhibit similar properties, making them a great sample of local analogs for high redshift galaxies. Further analysis of these extreme galaxies can allow us to uncover properties such as tem- perature, star formation rate, metallicity, gas density and production rate of ionizing radiation. These galactic properties can help us improve our understanding of galaxy evolution and the role galaxies may have played during reionization.
- Publication:
-
American Astronomical Society Meeting Abstracts #235
- Pub Date:
- January 2020
- Bibcode:
- 2020AAS...23520810C