Can pre-supernova winds from massive stars enrich the interstellar medium with nitrogen at high redshift?

Abstract

Understanding the nucleosynthetic origin of nitrogen and the evolution of the N/O ratio in the interstellar medium is crucial for a comprehensive picture of galaxy chemical evolution at high-redshift because most observational metallicity (O/H) estimates are implicitly dependent on the N/O ratio. The observed N/O at high-redshift shows an overall constancy with O/H, albeit with a large scatter. We show that these heretofore unexplained features can be explained by the pre-supernova wind yields from rotating massive stars (M≳10M⊙,ν/νcrit≳0.4). Our models naturally produce the observed N/O plateau, as well as the scatter at low O/H. We find the scatter to arise from varying star formation efficiency. However, the models that have supernovae dominated yields produce a poor fit to the observed N/O at low O/H. This peculiar abundance pattern at low O/H suggests that dwarf galaxies are most likely to be devoid of SNe yields and are primarily enriched by pre-supernova wind abundances.

Detection of Metal Enrichment by SN 2011jm in NGC 4809

“…The historical classification of CCSNe mainly divides them into two types: hydrogen-poor (stripped-envelope) Type Ibc SNe and hydrogen-rich Type II SNe. These explosive events eject heavy elements created during core nuclear burning (e.g., Hoyle & Fowler 1960;Nomoto et al 2006;Johnson 2019), leading to the chemical enrichment of the interstellar medium (ISM; e.g., Timmes et al 1995;Roy et al 2022) and potentially influencing the formation of new stars (e.g., Thornton et al 1998). CCSNe play a crucial role in the formation and distribution of chemical elements during the evolution of galaxies (e.g., Scannapieco et al 2008;Kuncarayakti et al 2013;Niino et al 2015;Kuncarayakti et al 2018;Xiao et al 2019;Ganss et al 2022;Sarbadhicary et al 2022;Kourniotis et al 2023;Molero et al 2023).…”