Theoretical Evolution of Optical Strong Lines across Cosmic Time

Understand

We use the chemical evolution predictions of cosmological hydrodynamic simulations with our latest theoretical stellar population synthesis, photoionization and shock models to predict the strong line evolution of ensembles of galaxies from z=3 to the present day.

• In this paper, we focus on the brightest optical emission-line ratios, [NII]/H-alpha and [OIII]/H-beta.
• We use the optical diagnostic Baldwin-Phillips-Terlevich (BPT) diagram as a tool for investigating the spectral properties of ensembles of active galaxies.
• We use four redshift windows chosen to exploit new near-infrared multi-object spectrographs.