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Ultraluminous X-ray bursts in two ultracompact companions to nearby elliptical galaxies
Nature (2016)
  • Jimmy A. Irwin, University of Alabama - Tuscaloosa
  • W. Peter Maksym, Harvard–Smithsonian Center for Astrophysics
  • Gregory R. Sivakoff, University of Alberta
  • Aaron J. Romanowsky, San Jose State University
  • Dacheng Lin, University of New Hampshire, Durham
  • Tyler Speegle, University of Alabama - Tuscaloosa
  • Ian Prado, University of Alabama - Tuscaloosa
  • David Mildebrath, University of Alabama - Tuscaloosa
  • Jay Strader, Michigan State University
  • Jifeng Liu, National Astronomical Observatories, Chinese Academy of Sciences
  • Jon M. Miller, The University Of Michigan
A search of archival X-ray data for 70 nearby galaxies has yielded two flaring sources in globular clusters or ultracompact dwarf companions of parent elliptical galaxies. One source flared once, and the other five times. When not flaring, these sources appear to be normal accreting neutron-star or black-hole X-ray binaries. Unlike magnetars and other bodies that produce repetitive flares of similar luminosity, they are located in old stellar populations.
  • Galaxies and clusters,
  • High-energy astrophysics
Publication Date
October 20, 2016
Publisher Statement
This is the Accepted Manuscript of an article that was published in Nature, volume 538, 2016. The Version of Record is available online at this link:

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Citation Information
Jimmy A. Irwin, W. Peter Maksym, Gregory R. Sivakoff, Aaron J. Romanowsky, et al.. "Ultraluminous X-ray bursts in two ultracompact companions to nearby elliptical galaxies" Nature Vol. 538 (2016) p. 356 - 358 ISSN: 1476-4687
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