http://arxiv.org/abs/2102.12343
Using a large sample of sub-L$*$ galaxies, with similar UV magnitudes, M${\rm UV}\simeq -19$ at $z\simeq6$, extracted from the FirstLight simulations, we show the diversity of galaxies at the end of the reionization epoch. We find a factor $\sim$40 variation in the specific star-formation rate (sSFR). This drives a $\sim$1 dex range in equivalent width of the [OIII]$\lambda$5007 line. Variations in nebular metallicity and ionization parameter within HII regions lead to a scatter in the equivalent widths and [OIII]/H$\alpha$ line ratio at a fixed sSFR. [OIII]-bright emitters have higher ionization parameters and/or higher metallicities than H$\alpha$-bright galaxies. According to the surface brightness maps in both [OIII] and H$\alpha$, [OIII]-bright emitters are more compact than H$\alpha$-bright galaxies. H$\alpha$ luminosity is higher than [OIII] if star formation is distributed over extended regions. OIII dominates if it is concentrated in compact clumps. In both cases, the H$\alpha$-emitting gas is significantly more extended than [OIII].
D. Ceverino, M. Hirschmann, R. Klessen, et. al.
Thu, 25 Feb 21
15/50
Comments: 9 pages, 5 figures, submitted to MNRAS. The website of the FirstLight database can be found at this https URL
You must be logged in to post a comment.