2025MNRAS.543.1158A -
Mon. Not. R. Astron. Soc., 543, 1158-1177 (2025/October-3)
Runaway status and origins of Galactic Wolf-Rayet stars - I. Late-type WN stars.
ARTHUR S.J.
Abstract (from CDS):
We use Gaia DR3 astrometric data and radial velocities from the literature to identify runaway stars from a sample of 90 Galactic late-type WN (WNL) stars. Runaways must either have peculiar velocities greater than 30 km s$^{-1}$ or be located at a vertical distance greater than the scale height for OB stars from the Galactic mid-plane. We find that 40 out of 90 stars meet either or both of these criteria, of which 6 are confirmed spectroscopic binary systems. Four sources have peculiar velocities above 100 km s$^{-1}$ and two of these are binary systems. The majority of the runaway WNL stars can be traced back to spiral arms in the thin disc within a typical massive star lifetime. For other sources, inferred kinematic ages in excess of 7 Myr suggest that binary evolution, including mass transfer, has played an important role in their lives. We find that the WN8 sub-type has a higher proportion of high-velocity runaways than the WN7 sub-type, indicating that these sub-types do not form an evolutionary sequence. Detailed examination of the Cygnus region suggests that at least some runaways could be a consequence of the formation process of young clusters from a parent turbulent molecular cloud, in addition to the more widely studied binary supernova and dynamical ejection scenarios (BSS and DES).
Abstract Copyright:
© The Author(s) 2025. Published by Oxford University Press on behalf of Royal Astronomical Society.
Journal keyword(s):
binaries: spectroscopic - stars: evolution - stars: kinematics and dynamics - stars: Wolf-Rayet
Simbad objects:
106
Full paper
View the references in ADS
To bookmark this query, right click on this link: simbad:2025MNRAS.543.1158A and select 'bookmark this link' or equivalent in the popup menu