N/O-trends in Late-Type Galaxies: AGB-stars, IMFs, Abundance Gradients and the Origin of Nitrogen

TL;DR

This paper investigates how the initial mass function and intermediate-mass stars influence nitrogen and oxygen abundance gradients in late-type galaxies, using chemical evolution models to understand nitrogen origins.

Contribution

It demonstrates that N/O abundance gradients can be used to constrain nitrogen contributions from intermediate-mass and AGB stars in galaxy evolution models.

Findings

N/O gradients are sensitive to the nitrogen contribution from IM/AGB stars.

Different IMFs and star formation prescriptions affect the modeled abundance gradients.

N/O gradients can serve as constraints on nitrogen production sources.

Abstract

Models of galactic chemical evolution (CEMs) show that the shape of the stellar initial mass function (IMF) and other assumptions regarding star formation affect the resultant abundance gradients in models of late-type galaxies. Furthermore, intermediate mass (IM) stars undeniably play an important role in the buildup of nitrogen abundances in galaxies. Here I specifically discuss the nitrogen contribution from IM/AGB stars and how it affects the N/O-gradient. For this purpose I have modelled the chemical evolution of a few nearby disc galaxies using different IMFs and star formation prescriptions. It is demonstrated that N/O-gradients may be used to constrain the nitrogen contribution from IM/AGB-stars.