Very Massive Stars (VMS) in the Local Universe

TL;DR

This paper reviews recent claims of very massive stars up to 300 solar masses in the local universe, discussing their data, formation, evolution, and implications for stellar mass limits.

Contribution

It provides a comprehensive discussion on the current evidence, formation mechanisms, and evolutionary paths of very massive stars, aiming to unify observational and theoretical perspectives.

Findings

Evidence for stars up to 300 solar masses

Discussion on formation and mass loss mechanisms

Implications for stellar upper-mass limit

Abstract

Recent studies have claimed the existence of very massive stars (VMS) up to 300 solar masses in the local Universe. As this finding may represent a paradigm shift for the canonical stellar upper-mass limit of 150 Msun, it is timely to discuss the status of the data, as well as the far-reaching implications of such objects. We held a Joint Discussion at the General Assembly in Beijing to discuss (i) the determination of the current masses of the most massive stars, (ii) the formation of VMS, (iii) their mass loss, and (iv) their evolution and final fate. The prime aim was to reach broad consensus between observers and theorists on how to identify and quantify the dominant physical processes.