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arXiv · 1603.00744

Suzaku observations of the 2013 outburst of KS 1947+300

Ralf Ballhausen·Matthias Kühnel·Katja Pottschmidt·Felix Fürst·Paul B. Hemphill·Sebastian Falkner·Amy M. Gottlieb·Victoria Grinberg·Peter Kretschmar·Ingo Kreykenbohm·Richard E. Rothschild·Jörn Wilms
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Abstract

We report on the timing and spectral analysis of two Suzaku observations with different flux levels of the high-mass X-ray binary KS 1947+300 during its 2013 outburst. In agreement with simultaneous NuSTAR observations, the continuum is well described by an absorbed power law with a cut-off and an additional black body component. In addition we find fluorescent emission from neutral, He-like, and even H-like iron. We determine a pulse period of ~18.8 s with the source showing a spin-up between the two observations. Both Suzaku observations show a very similar behavior of the pulse profile, which is strongly energy dependent, with an evolution from a profile with one peak at low energies to a profile with two peaks of different widths towards higher energies seen in both, the Suzaku and NuSTAR data. Such an evolution to a more complex profile at higher energies is rarely seen in X-ray pulsars, most cases show the opposite behavior. Pulse phase-resolved spectral analysis shows a variation in the absorbing column density, NH , over pulse phase. Spectra taken during the pulse profile minima are intrinsically softer compared to the pulse phase-averaged spectrum.

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Ralf Ballhausen, Matthias Kühnel, Katja Pottschmidt, Felix Fürst, Paul B. Hemphill, Sebastian Falkner, Amy M. Gottlieb, Victoria Grinberg, Peter Kretschmar, Ingo Kreykenbohm, Richard E. Rothschild, Jörn Wilms. 2016-03-02. Suzaku observations of the 2013 outburst of KS 1947+300. https://doi.org/10.1051/0004-6361%2F201527193

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