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arXiv · 0805.3608

Discoveries of 3 K-shell Lines of Iron and a Coherent Pulsation of 593-sec from SAX J1748.2-2808

Masayoshi Nobukawa·Katsuji Koyama·Hironori Matsumoto·Takeshi Go Tsuru
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Abstract

SAX J1748.2$-$2808 is a unique X-ray object with a flat spectrum and strong emission lines at 6.4--7.0 keV. The Suzaku satellite resolved the emission lines into 3 K-shell lines from neutral and highly ionized irons. A clear coherent pulsation with a period of 593-sec was found from the Suzaku and XMM-Newton archives. These facts favor that SAX J1748.2$-$2808 isan intermediate polar, a subclass of magnetized white dwarf binary (cataclysmic variable: CV). This paper reports on details of the findings and discusses the origin of this source.

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Masayoshi Nobukawa, Katsuji Koyama, Hironori Matsumoto, Takeshi Go Tsuru. 2008-06-23. Discoveries of 3 K-shell Lines of Iron and a Coherent Pulsation of 593-sec from SAX J1748.2-2808. https://doi.org/10.1093/pasj%2F61.sp1.s93

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