MIT Libraries logoDSpace@MIT

MIT
View Item 
  • DSpace@MIT Home
  • MIT Open Access Articles
  • MIT Open Access Articles
  • View Item
  • DSpace@MIT Home
  • MIT Open Access Articles
  • MIT Open Access Articles
  • View Item
JavaScript is disabled for your browser. Some features of this site may not work without it.

HIGH-RESOLUTION X-RAY SPECTROSCOPY REVEALS THE SPECIAL NATURE OF WOLF-RAYET STAR WINDS

Author(s)
Oskinova, Lidia M.; Gayley, K. G.; Hamann, W.-R.; Ignace, R.; Pollock, A. M. T.; Huenemoerder, David P.; ... Show more Show less
Thumbnail
DownloadOskinova-2012-HIGH-RESOLUTION X-RA.pdf (644.8Kb)
PUBLISHER_POLICY

Publisher Policy

Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.

Terms of use
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
Metadata
Show full item record
Abstract
We present the first high-resolution X-ray spectrum of a putatively single Wolf-Rayet (WR) star. 400 ks observations of WR 6 by the XMM-Newton telescope resulted in a superb quality high-resolution X-ray spectrum. Spectral analysis reveals that the X-rays originate far out in the stellar wind, more than 30 stellar radii from the photosphere, and thus outside the wind acceleration zone where the line-driving instability (LDI) could create shocks. The X-ray emitting plasma reaches temperatures up to 50 MK and is embedded within the unshocked, "cool" stellar wind as revealed by characteristic spectral signatures. We detect a fluorescent Fe line at ≈6.4 keV. The presence of fluorescence is consistent with a two-component medium, where the cool wind is permeated with the hot X-ray emitting plasma. The wind must have a very porous structure to allow the observed amount of X-rays to escape. We find that neither the LDI nor any alternative binary scenario can explain the data. We suggest a scenario where X-rays are produced when the fast wind rams into slow "sticky clumps" that resist acceleration. Our new data show that the X-rays in single WR star are generated by some special mechanism different from the one operating in the O-star winds.
Date issued
2012-02
URI
http://hdl.handle.net/1721.1/95464
Department
MIT Kavli Institute for Astrophysics and Space Research
Journal
The Astrophysical Journal. Letters
Publisher
IOP Publishing
Citation
Oskinova, L. M., K. G. Gayley, W.-R. Hamann, D. P. Huenemoerder, R. Ignace, and A. M. T. Pollock. “HIGH-RESOLUTION X-RAY SPECTROSCOPY REVEALS THE SPECIAL NATURE OF WOLF-RAYET STAR WINDS.” The Astrophysical Journal 747, no. 2 (February 21, 2012): L25. © 2012 The American Astronomical Society
Version: Final published version
ISSN
2041-8205
2041-8213

Collections
  • MIT Open Access Articles

Browse

All of DSpaceCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

My Account

Login

Statistics

OA StatisticsStatistics by CountryStatistics by Department
MIT Libraries
PrivacyPermissionsAccessibilityContact us
MIT
Content created by the MIT Libraries, CC BY-NC unless otherwise noted. Notify us about copyright concerns.