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Compton Scattering of Fe KαLines from Accreting White Dwarfs

Z. Kuncic·K. Wu·J. G. Cullen
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Abstract

Compton scattering in the bulk accretion flow of the accretion column in magnetic cataclysmic variables (mCVs) can significantly shift photon energies in the X-ray emission lines resulting from accretion shocks. In particular, Compton recoil can potentially broaden the 6.7 and 6.97 keV Fe K$α$ emission lines produced in the post-shock region, and contaminate the fluorescent 6.4 keV neutral Fe K$α$ line reflected off the white dwarf surface. We present nonlinear Monte Carlo simulations demonstrating these effects, and we discuss the interpretation of observed Fe K$α$ linewidths in mCVs in light of these new results. The implications for other accreting compact objects are also discussed.

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Z. Kuncic, K. Wu, J. G. Cullen. 2004-11-14. Compton Scattering of Fe KαLines from Accreting White Dwarfs. https://doi.org/10.1071/as04071

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