Mass loss and evolution of hot massive stars

TL;DR

This paper reviews how mass loss influences the evolution of massive stars, focusing on phenomena like the bi-stability jump, wind variations in LBVs, and metallicity effects, with implications for supernovae and gamma-ray bursts.

Contribution

It provides a comprehensive discussion of mass loss mechanisms and their impact on the evolution and observational features of hot massive stars, including new insights into bi-stability jumps and wind variability.

Findings

Bi-stability jump affects stellar rotational velocities.

Wind variations in LBVs relate to supernova modulations.

Metallicity influences stellar wind strength and evolution.

Abstract

We discuss the role of mass loss for the evolution of the most massive stars, highlighting the role of the predicted bi-stability jump that might be relevant for the evolution of rotational velocities during or just after the main sequence. This mechanism is also proposed as an explanation for the mass-loss variations seen in the winds from Luminous Blue Variables (LBVs). These might be relevant for the quasi-sinusoidal modulations seen in a number of recent transitional supernovae (SNe), as well as for the double-throughed absorption profile recently discovered in the Halpha line of SN 2005gj. Finally, we discuss the role of metallicity via the Z-dependent character of their winds, during both the initial and final (Wolf-Rayet) phases of evolution, with implications for the angular momentum evolution of the progenitor stars of long gamma-ray bursts (GRBs).