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arXiv · 1905.09496

Cyclotron emission, absorption, and the two faces of X-ray pulsar A 0535+262

Sergey S. Tsygankov·Victor Doroshenko·Alexander A. Mushtukov·Valery F. Suleimanov·Alexander A. Lutovinov·Juri Poutanen
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Abstract

Deep NuSTAR observation of X-ray pulsar A 0535+262, performed at a very low luminosity of $\sim7\times10^{34}$ erg s$^{-1}$, revealed the presence of two spectral components. We argue that the high-energy component is associated with cyclotron emission from recombination of electrons collisionally excited to the upper Landau levels. The cyclotron line energy of $E_{\rm cyc}=47.7\pm0.8$ keV was measured at the luminosity of almost an order of magnitude lower than what was achieved before. The data firmly exclude a positive correlation of the cyclotron energy with the mass accretion rate in this source.

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Sergey S. Tsygankov, Victor Doroshenko, Alexander A. Mushtukov, Valery F. Suleimanov, Alexander A. Lutovinov, Juri Poutanen. 2019-05-23. Cyclotron emission, absorption, and the two faces of X-ray pulsar A 0535+262. https://doi.org/10.1093/mnrasl%2Fslz079

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