SWIFT J0503.7-2819: A nearly synchronous intermediate polar below the period gap?

Rawat, Nikita; Pandey, JC; Joshi, Arti; Scaringi, Simone; Yadava, Umesh

Abstract

Based on the X-ray observations from XMM-Newton and Swift, and optical observations from Transiting Exoplanet Survey Satellite (TESS) and AAVSO, we present temporal and spectral properties of probable intermediate polar SWIFT J0503.7-2819. The X-ray light curve shows two distinctive features, where possibly the second pole seems to be active during the middle of the XMM-Newton observations. Present analysis confirms and also refines the previously reported orbital period of SWIFT J0503.7-2819 as 81.65±0.04 min. The X-ray and optical variations of this target have been found to occur at the period of ∼ 65 min, which we propose as the spin period of the white dwarf (WD). The energy-dependent modulation at this period, which are due to the photoelectric absorption in the accretion flow, also assures this conjecture. Two temperature thermal plasma model well explains the X-ray spectra with temperatures of ∼ 150 eV and ∼ 18.5 keV, which is absorbed by a dense material with an average equivalent hydrogen column density of 3.8 × 1022 cm−2 that partially covers ∼ 27% of the X-ray source. An attempt is made to understand the accretion flow in this system using the present data of SWIFT J0503.7-2819. If the proposed spin period is indeed the actual period, then SWIFT J0503.7-2819 could be the first nearly synchronous intermediate polar below the period gap.

Citation

Rawat, N., Pandey, J., Joshi, A., Scaringi, S., & Yadava, U. (2022). SWIFT J0503.7-2819: A nearly synchronous intermediate polar below the period gap?. Monthly Notices of the Royal Astronomical Society, 517(2), 1667-1677. https://doi.org/10.1093/mnras/stac2723

• Journal Article Type: Article
• Publication Date: 2022-12
• Deposit Date: Oct 11, 2022
• Publicly Available Date: Mar 31, 2023
• Journal: Monthly Notices of the Royal Astronomical Society
• Print ISSN: 0035-8711
• Electronic ISSN: 1365-2966
• Publisher: Royal Astronomical Society
• Peer Reviewed: Peer Reviewed
• Volume: 517
• Issue: 2
• Pages: 1667-1677
• DOI: https://doi.org/10.1093/mnras/stac2723
• Public URL: https://durham-repository.worktribe.com/output/1189803