Confirmation of 1RXS J165443.5-191620 as an intermediate polar and its orbital and spin periods

Abstract

Aims: We investigate the physical nature of the X-ray emitting source 1RXS J165443.5-191620 through optical photometry and time-resolved spectroscopy. Methods: Optical photometry is obtained from a variety of telescopes all over the world spanning about 27 days. Additionally, time-resolved spectroscopy is obtained from the MDM observatory. Results: The optical photometry clearly displays modulations consistent with those observed in magnetic cataclysmic variables: a low-frequency signal interpreted as the orbital period, a high-frequency signal interpreted as the white dwarf spin period, and an orbital sideband modulation. Our findings and interpretations are further confirmed through optical, time-resolved, spectroscopy that displays H-alpha radial velocity shifts modulated on the binary orbital period. Conclusion: We confirm the true nature of 1RXS J165443.5-191620 as an intermediate polar with a spin period of 546 seconds and an orbital period of 3.7 hours. In particular, 1RXS J165443.5-191620 is part of a growing subset of intermediate polars, all displaying hard X-ray emission above 15keV, white dwarf spin periods below 30 minutes, and spin-to-orbital ratios below 0.1.

7 pages, 9 figures, 6 tables, accepted for publication in A&A

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Cited by in corpus (9)

• Magnetic White Dwarfs
• Characterization of new hard X-ray Cataclysmic Variables
• On the nature of the hard X-ray sources SWIFTJ1907.3-2050, IGRJ12123-5802 and IGRJ19552+0044
• Identifying IGR J14091-6108 as a magnetic CV with a massive white dwarf using X-ray and optical observations
• IPHAS J062746.41+014811.3: a deeply eclipsing intermediate polar
• The Magnetospheric Boundary in Cataclysmic Variables
• An intermediate polar candidate toward the Galactic plane
• Very fast photometric and X-ray observations of the intermediate polar V2069 Cygni (RX J2123.7+4217)
• X-ray confirmation of the intermediate polar IGR J16547-1916