The Diagnostic Potential of Co-rotating Interaction Regions in Dense Hot-Star Winds

Wolf-Rayet (WR) stars exhibit strong, high-velocity winds with small-scale stochastic clumps and large-scale structures like Co-rotating Interaction Regions (CIRs). CIRs are spiral-shaped density enhancements, which propagate through the wind and induce variability in spectropolarimetric signals. WR6 (EZ CMa, WN4b) is a well-studied target with a stable 3.76-day periodicity in its wind variations. Recent observations, including linear spectropolarimetry, reveal distinct patterns in the Stokes Q-U plane, suggesting a complex, asymmetric scattering envelope.

Current modeling efforts, such as those by Dr. Richard Ignace, provide proof-of-concept frameworks for interpreting spectropolarimetric data. However, these models require refinement and validation through deeper observational insights. The proposed research seeks to advance the synergy between observations and modeling to uncover the mechanisms behind these variations, a critical step in understanding massive-star evolution and feedback.

Faculty Supervisor:

Nicole St-Louis

Student:

Partner:

University of Iowa

Discipline:

Physics

Sector:

Education

University:

Université de Montréal

Program: