Changes in the cyclotron line energy on short and long timescales in V 0332+53

  title={Changes in the cyclotron line energy on short and long timescales in V 0332+53},
  author={Vadim Vybornov and V Doroshenko and R. Staubert and Andrea Santangelo},
  journal={Astronomy and Astrophysics},
We present the results of the pulse-amplitude-resolved spectroscopy of the accreting pulsar V 0332+53 using the NuSTAR observations of the source in 2015 and 2016. We investigate the dependence of the energy of the cyclotron resonant scattering feature (CRSF) as a function of X-ray luminosity on timescales comparable with the spin period of the pulsar within individual observations, and the behavior on longer timescales within and between the two observed outbursts. We confirm that in both… 

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