Massive stars in the nuclei and arms of spirals

TL;DR

This paper reviews recent findings on the properties and content of massive stars in nearby spiral galaxies, focusing on ionized gas analysis, Wolf-Rayet signatures, and chemical abundances, especially in high-metallicity regions.

Contribution

It provides a comprehensive review of how giant H II regions reveal the characteristics of massive stars and their chemical environments in spiral galaxy nuclei and arms.

Findings

Detection of Wolf-Rayet features in extragalactic H II regions

Chemical abundance comparisons between supergiant stars and ionized gas

Insights into metallicity effects on massive star properties

Abstract

Many of the properties of massive stars in external galaxies, such as chemical compositions, mass functions, and ionizing fluxes, can be derived from the study of the associated clouds of ionized gas. Moreover, the signatures of Wolf-Rayet stars are often detected in the spectra of extragalactic H II regions. This paper reviews some aspects of the recent work on the massive star content of nearby spiral galaxies, as inferred from the analysis of giant H II regions. Particular attention is given to regions of high metallicity, including nuclear hot spots, and to the chemical abundance comparison between supergiant stars and ionized gas.