Galactic consequences of clustered star formation

TL;DR

This paper explores how the distribution of star cluster masses influences the overall stellar mass function in galaxies, affecting their chemical and photometric properties.

Contribution

It demonstrates that the galaxy-wide stellar mass function (IGIMF) is steeper at high masses due to clustered star formation and analyzes how sampling methods impact this steepness.

Findings

IGIMF is steeper at high masses than the underlying IMF.

The steepness depends on sampling methods and cluster mass function assumptions.

Galaxies' chemical enrichment and O-star content are affected by the IGIMF.

Abstract

If all stars form in clusters and both the stars and the clusters follow a power law distribution which favours the creation of low mass objects, then the numerous low mass clusters will be deficient in high mass stars. Therefore, the mass function of stars, integrated over the whole galaxy (the Integrated Galactic Initial Mass Function, IGIMF) will be steeper at the high mass end than the underlying IMF of the stars. We show how the steepness of the IGIMF depends on the sampling method and on the assumptions made for the star cluster mass function. We also investigate the O-star content, integrated photometry and chemical enrichment of galaxies that result from several IGIMFs, as compared to more standard IMFs.