Kinematics of Wolf-Rayet Stars in the LMC: Clues to Subtype Origins

Abstract

We measure transverse proper motion velocities of LMC Wolf-Rayet (WR) stars using Gaia DR3 astrometry. The combined velocity distribution of WNh, O If*/WN, and WNL very massive stars ($>100M_{\odot }$; VMS) shows both slow, unejected objects ($v_{\perp }<10$ $\mathrm{km}{\mathrm{s}}^{-1}$) and stars dominated by fast, runaway velocities ($v_{\perp }>24$ $\mathrm{km}{\mathrm{s}}^{-1}$). This supports expectations that VMS ages are comparable to the dynamical ejection timescale ($\sim 1.5$ Myr). These kinematics share similarities with those of lower-luminosity, classical WNh, O If*/WN, and WNL stars, as well as the SMC field OB stars, suggesting that dynamical ejections may also dominate these populations. In contrast, both single and binary WNE stars are ejected populations that show single-peaked velocity distributions, suggesting a different ejection mechanism(s). We speculate that single WNE stars might result from explosive mergers onto the shell-burning layer, thereby stripping the H envelope. Binary WC stars appear to be faster (median $v_{\perp }=54$ $\mathrm{km}{\mathrm{s}}^{-1}$) and have higher luminosities than singles (median $v_{\perp }=38$ $\mathrm{km}{\mathrm{s}}^{-1}$), suggesting that single WC stars are not descendants of the binaries. Thus, the binaries are probably stripped by mass transfer, while the WC singles likely originate from another process. The high velocities of binary WC stars are consistent with some predictions that lower mass clusters generate fast dynamical ejections. Single WC and WN3/O3 stars have ambiguous kinematics, but both show high $v_{\perp }$ (median $\sim 38$ $\mathrm{km}{\mathrm{s}}^{-1}$), possibly linked to their lower masses.

arXiv comment33 pages, 15 Figures, 3 Tables. Accepted 2026 March 16

References in corpus (72)

• The Gaia mission
• Gaia Data Release 3: Summary of the content and survey properties
• Binary interaction dominates the evolution of massive stars
• Pre-Supernova Evolution of Massive Single and Binary Stars
• Gaia Early Data Release 3: Photometric content and validation
• A distance to the Large Magellanic Cloud that is precise to one per cent
• The R136 star cluster hosts several stars whose individual masses greatly exceed the accepted 150 Msun stellar mass limit
• On the metallicity dependence of Wolf-Rayet winds
• On the origin of the O and B-type stars with high velocities II Runaway stars and pulsars ejected from the nearby young stellar groups
• Massive runaways and walkaway stars
• Runaway stars as progenitors of supernovae and gamma-ray bursts
• The R136 star cluster dissected with Hubble Space Telescope/STIS. I. Far-ultraviolet spectroscopic census and the origin of HeII 1640 in young star clusters
• Mass loss from late-type WN stars and its Z-dependence: very massive stars approaching the Eddington limit
• The Wolf-Rayet stars in the Large Magellanic Cloud: A comprehensive analysis of the WN class
• Wind modelling of very massive stars up to 300 solar masses
• Delay-time distribution of core-collapse supernovae with late events resulting from binary interaction
• The Origin of OB Runaway Stars
• The Eddington factor as the key to understand the winds of the most massive stars. Evidence for a Gamma-dependence of Wolf-Rayet type mass loss
• Luminous Blue Variables and superluminous supernovae from binary mergers
• Ionizing spectra of stars that lose their envelope through interaction with a binary companion: role of metallicity
• Statistical Confirmation of a Stellar Upper Mass Limit
• The VLT-FLAMES Tarantula Survey - XI. A census of the hot luminous stars and their feedback in 30 Doradus
• Dynamical ejections of massive stars from young star clusters under diverse initial conditions
• Spectral Classification of O2-3.5If*/WN5-7 stars
• Structure and evolution of high-mass stellar mergers
• Why binary interaction does not necessarily dominate the formation of Wolf-Rayet stars at low metallicity
• On the role of the WNH phase in the evolution of very massive stars: Enabling the LBV instability with feedback
• Dependency of dynamical ejections of O stars on the masses of very young star clusters
• The VLT-FLAMES Tarantula Survey. XXIX. Massive star formation in the local 30 Doradus starburst
• Common envelope events with low-mass giants: understanding the transition to the slow spiral-in
• A Modern Search for Wolf-Rayet Stars in the Magellanic Clouds. IV. A Final Census
• Properties of WNh stars in the Small Magellanic Cloud: evidence for homogeneous evolution
• The emergence of super-canonical stars in R136-type star-burst clusters
• Explosive Common-Envelope Ejection: Implications for Gamma-Ray Bursts and Low-Mass Black-Hole Binaries
• Two step ejection of massive stars and the issue of their formation in isolation
• The quest for blue supergiants: binary merger models for the evolution of the progenitor of SN 1987A
• Hydrodynamical Simulations of the Stream-Core Interaction in the Slow Merger of Massive Stars
• Helium Stars: Towards an Understanding of Wolf-Rayet Evolution
• The spectroscopic Hertzsprung-Russell diagram of hot massive stars in the SMC
• Gaia DR2 reveals a very massive runaway star ejected from R136
• Runaway OB Stars in the Small Magellanic Cloud: Dynamical Versus Supernova Ejections
• Fast & slow winds from supergiants and Luminous Blue Variables
• Resolved Kinematics of Runaway and Field OB Stars in the Small Magellanic Cloud
• Wolf-Rayet and O Star Runaway Populations from Supernovae
• Galactic runaway O and Be stars found using Gaia DR3
• A synthetic population of Wolf-Rayet stars in the LMC based on detailed single and binary star evolution models
• The Evolution and Physical Parameters of WN3/O3s: a New Type of Wolf-Rayet Star
• WO-Type Wolf-Rayet Stars: the Last Hurrah of Massive Star Evolution
• The isolation of Luminous Blue Variables: On subdividing the sample
• The VLT-FLAMES Tarantula Survey: Observational evidence for two distinct populations of massive runaway stars in 30 Doradus
• CNO driven winds of hot first stars
• Gaia and HST astrometry of the very massive $\sim$150 $M_{\odot }$ candidate runaway star VFTS682
• Extreme isolation of WN3/O3 stars and implications for their evolutionary origin as the elusive stripped binaries
• Star Cluster Formation from Turbulent Clumps. II. Gradual Star Cluster Formation
• The Slow Merger of Massive Stars
• Two waves of massive stars running away from the young cluster R136
• Reverse Algols and hydrogen-rich Wolf-Rayet stars from very massive binaries
• Helium and Nitrogen Enrichment in Massive Main Sequence Stars: Mechanisms and Implications for the Origin of WNL Stars
• Star Cluster Formation from Turbulent Clumps. III. Across the mass spectrum
• The Physical Parameters of Four WC-type Wolf-Rayet Stars in the Large Magellanic Cloud: Evidence of Evolution
• Populations of evolved massive binary stars in the Small Magellanic Cloud II: Predictions from rapid binary evolution
• A Multiwavelength Survey of Wolf-Rayet Nebulae in the Large Magellanic Cloud
• The population synthesis of Wolf-Rayet stars involving binary merger channels
• Close binary evolution based on Gaia DR2: the origin of late WC-type Wolf-Rayet stars with low luminosity
• Constraints on the Binarity of the WN3/O3 Class of Wolf-Rayet Stars
• Very massive stars at low metallicity: evolution, synthetic spectroscopy, and impact on the integrated light of starbursts
• An observational study of rotation and binarity of Galactic O-type runaway stars
• Stellar ejection velocities from the binary supernova scenario: A comparison across population synthesis codes
• New Field OB and OBe Binaries of the SMC Wing: Observational Properties and Population Modeling
• The evolution of accretor stars in binary systems due to accretion of increasingly helium-rich material
• The origin of the most recently ejected OB runaway star from the R136 cluster
• Long GRBs from binary stars: runaway, Wolf-Rayet progenitors