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arXiv · astro-ph/0609245

An Apparent Hard X-ray Decline of CH Cygni

Koji Mukai·Manabu Ishida·Caroline Kilbourne·Hideyuki Mori·Yukikatsu Terada·Kai-Wing Chan·Yang Soong
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Abstract

CH Cygni is a symbiotic star consisting of an M giant and an accreting white dwarf, which is known to be a highly variable X-ray source with a complex, two-component, spectra. Here we report on two Suzaku observations of CH Cyg, taken in 2006 January and May, during which the system was seen to be in a soft X-ray bright, hard X-ray faint state. Based on the extraordinary strength of the 6.4 keV fluorescent Fe K-alpha line, we show that the hard X-rays observed with Suzaku are dominated by scattering.

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Koji Mukai, Manabu Ishida, Caroline Kilbourne, Hideyuki Mori, Yukikatsu Terada, Kai-Wing Chan, Yang Soong. 2006-09-08. An Apparent Hard X-ray Decline of CH Cygni. https://doi.org/10.1093/pasj%2F59.sp1.s177

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