The variable cyclotron line in GX 301-2

  title={The variable cyclotron line in GX 301-2},
  author={Ingo Kreykenbohm and Joern Wilms and Wayne Coburn and Markus Kuster and Richard E. Rothschild and William Adams Heindl and Peter Kretschmar and Ruediger Staubert},
  journal={Astronomy and Astrophysics},
We present pulse phase resolved spectra of the hypergiant high mass X-ray binary GX 301−2. We observed the source in 2001 October with RXTE continuously for a total on-source time of almost 200 ks. We model the continuum with both, a heavily absorbed partial covering model and a reflection model. In either case we find that the well known cyclotron resonant scattering feature (CRSF) at ∼35 keV is - although present at all pulse phases - strongly variable over the pulse: the line position varies… Expand
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