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

TL;DR

This study reports the detection of three iron K-shell emission lines and a 593-second pulsation from SAX J1748.2-2808, suggesting it is an intermediate polar type of magnetized white dwarf binary.

Contribution

The paper provides the first resolution of iron emission lines and confirms the pulsation, supporting the classification of SAX J1748.2-2808 as an intermediate polar CV.

Findings

Resolved three iron K-shell lines from the source.

Detected a coherent 593-sec pulsation.

Supported the intermediate polar classification.

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.