Extreme isolation of WN3/O3 stars and implications for their evolutionary origin as the elusive stripped binaries
Publisher
OXFORD UNIV PRESSCitation
Nathan Smith, Ylva Götberg, Selma E de Mink; Extreme isolation of WN3/O3 stars and implications for their evolutionary origin as the elusive stripped binaries, Monthly Notices of the Royal Astronomical Society, Volume 475, Issue 1, 21 March 2018, Pages 772–782, https://doi.org/10.1093/mnras/stx3181Rights
© 2017 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society.Collection Information
This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu.Abstract
Recent surveys of the Magellanic Clouds have revealed a subtype of Wolf-Rayet (WR) star with peculiar properties. WN3/O3 spectra exhibit both WR-like emission and O3 V-like absorption - but at lower luminosity than O3 V or WN stars. We examine the projected spatial distribution of WN3/O3 stars in the Large Magellanic Cloud as compared to O-type stars. Surprisingly, WN3/O3 stars are among the most isolated of all classes of massive stars; they have a distribution similar to red supergiants dominated by initial masses of 10(-15) M, and are far more dispersed than classical WR stars or luminous blue variables. Their lack of association with clusters of O-type stars suggests strongly that WN3/O3 stars are not the descendants of single massive stars (30 M circle dot or above). Instead, they are likely products of interacting binaries at lower initial mass (10-18 M circle dot). Comparison with binary models suggests a probable origin with primaries in this mass range that were stripped of their H envelopes through non-conservative mass transfer by a low-mass secondary. We show that model spectra and positions on the Hertzsprung-Russell diagram for binary-stripped stars are consistent with WN3/O3 stars. Monitoring radial velocities with high-resolution spectra can test for low-mass companions or runaway velocities. With lower initial mass and environments that avoid very massive stars, the WN3/O3 stars fit expectations for progenitors of Type Ib and possibly Type Ibn supernovae.ISSN
0035-87111365-2966
Version
Final published versionSponsors
NSF [AST-1312221, AST-1515559]; Research Corporation for Science Advancement; National Aeronautics and Space Administration (NASA) through HST from the Space Telescope Science Institute [AR-14316]; NASA [NAS5-26555]; European Union's Horizon research and innovation programme [715063]; Marie Sklodowska-Curie [661502]; National Science Foundation [NSF PHY11-25915]Additional Links
http://academic.oup.com/mnras/article/475/1/772/4712244ae974a485f413a2113503eed53cd6c53
10.1093/mnras/stx3181