The True origin of Wolf-Rayet stars

TL;DR

This paper explores the fundamental causes of the Wolf-Rayet phenomenon, emphasizing radiation-driven winds and key stellar parameters, and discusses recent breakthroughs in understanding mass loss related to the Eddington factor, with implications for stellar evolution and high-redshift galaxies.

Contribution

It introduces new insights into the role of the Eddington factor in mass loss and the evolution of Wolf-Rayet stars, advancing understanding of their origin and behavior.

Findings

Breakthrough in understanding Gamma-dependent mass loss

Implications for evolution of massive stars

Potential for studying WR stars in high-redshift galaxies

Abstract

The Wolf-Rayet (WR) phenomenon is widespread in astronomy. It involves classical WRs, very massive stars (VMS), WR central stars of planetary nebula CSPN [WRs], and supernovae (SNe). But what is the root cause for a certain type of object to turn into an emission-line star? In this contribution, I discuss the basic aspects of radiation-driven winds that might reveal the ultimate difference between WR stars and canonical O-type stars. I discuss the aspects of (i) self-enrichment via CNO elements, (ii) high effective temperatures Teff, (iii) an increase in the helium abundance Y, and finally (iv) the Eddington factor Gamma. Over the last couple of years, we have made a breakthrough in our understanding of Gamma-dependent mass loss, which will have far-reaching consequences for the evolution and fate of the most massive stars in the Universe. Finally, I discuss the prospects for studies of the WR phenomenon in the highest redshift Ly-alpha and He II emitting galaxies.