Hiding in Plain Sight: Chandra Observations of the Quiescent Neutron Star 4U 2129+47 in Eclipse

  title={Hiding in Plain Sight: Chandra Observations of the Quiescent Neutron Star 4U 2129+47 in Eclipse},
  author={Michael A. Nowak and Sebastian Heinz and Mitchell C. Begelman},
  journal={The Astrophysical Journal},
  pages={778 - 788}
During a previous outburst phase, the neutron star 4U 2129+47 exhibited evidence for a spatially extended accretion disk corona via broad, partial X-ray eclipses occurring periodically on the 5.24 hr orbit. Since 1983, however, 4U 2129+47 has entered a quiescent state several orders of magnitude fainter. We have performed a 37 ks (≈two binary orbits) Chandra observation of 4U 2129+47 to determine whether an extended coronal structure also exists in quiescence. Total eclipses are found, and the… 


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