The role of massive stars in the turbulent infancy of Galactic globular clusters: Feedback on the intracluster medium, and detailed timeline

TL;DR

This paper reviews recent advances in understanding globular cluster formation, emphasizing the influence of massive stars on the intracluster medium and the development of multiple stellar populations within the first 40 million years.

Contribution

It presents a detailed timeline of early globular cluster evolution based on the Fast Rotating Massive stars scenario, integrating stellar feedback and bubble dynamics.

Findings

Multiple stellar populations identified through chemical and photometric analysis.

Massive stars significantly influence the intracluster medium and subsequent star formation.

A proposed timeline for the first 40 million years of globular cluster evolution.

Abstract

A major paradigm shift has recently revolutionized our picture of globular clusters (GC) that were long thought to be simple systems of coeval stars born out of homogeneous material. Indeed, detailed abundance studies of GC long-lived low-mass stars performed with 8-10m class telescopes, together with high-precision photometry of Galactic GCs obtained with HST,have brought compelling clues on the presence of multiple stellar populations in individual GCs. These stellar subgroups can be recognized thanks to their different chemical properties (more precisely by abundance differences in light elements from carbon to aluminium; see Bragaglia, this volume) and by the appearance of multimodal sequences in the colour-magnitude diagrams (see Piotto, this volume). This has a severe impact on our understanding of the early evolution of GCs, and in particular of the possible role that massive stars played in shaping the intra-cluster medium (ICM) and in inducing secondary star formation. Here we summarize the detailed timeline we have recently proposed for the first 40 Myrs in the lifetime of a typical GC following the general ideas of our so-called "Fast Rotating Massive stars scenario" (FRMS, Decressin et al. 2007b) and taking into account the dynamics of interstellar bubbles produced by stellar winds and supernovae. More details can be found in Krause et al. (2012, 2013).