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arXiv · 1407.0322

Probing the accretion processes in soft X-ray selected polars

I. Traulsen·K. Reinsch·A. D. Schwope
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Abstract

High-energy data of accreting white dwarfs give access to the regime of the primary accretion-induced energy release and the different proposed accretion scenarios. We perform XMM-Newton observations of polars selected due to their ROSAT hardness ratios close to -1.0 and model the emission processes in accretion column and accretion region. Our models consider the multi-temperature structure of the emission regions and are mainly determined by mass-flow density, magnetic field strength, and white-dwarf mass. To describe the full spectral energy distribution from infrared to X-rays in a physically consistent way, we include the stellar contributions and establish composite models, which will also be of relevance for future X-ray missions. We confirm the X-ray soft nature of three polars.

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I. Traulsen, K. Reinsch, A. D. Schwope. 2014-07-01. Probing the accretion processes in soft X-ray selected polars. https://arxiv.org/abs/1407.0322

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