A reevaluation of the proposed spin-down of the white dwarf pulsar in AR Scorpii

Abstract

We present high-speed optical photometric observations, spanning ~2 years, of the recently-discovered white dwarf pulsar AR Scorpii. The amplitudes of the orbital, spin and beat modulations appear to be remarkably stable and repeatable over the time span of our observations. It has been suggested that the polarized and non-polarized emission from AR Scorpii is powered by the spin-down of the white dwarf. However, we find that our new data is inconsistent with the published spin-down ephemeris. Whilst our data is consistent with a constant spin period further observations over an extended time-base are required in order to ascertain the true spin-evolution of the white dwarf.

arXiv commentAccepted for publication in MNRASL. 5 pages, 7 figures

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Cited by in corpus (11)

• High-Time-Resolution Photometry of AR Scorpii: Confirmation of the White Dwarf's Spin-Down
• Driving the Beat: Time-Resolved Spectra of the White Dwarf Pulsar AR Scorpii
• Long-term photometric monitoring and spectroscopy of the white dwarf pulsar AR Scorpii
• An Improved Spin-Down Rate for the Proposed White-Dwarf Pulsar AR Scorpii
• Constraining the Emission Geometry and Mass of the White Dwarf Pulsar AR Sco using the Rotating Vector Model
• Probing the Non-thermal Emission Geometry of AR Sco via Optical Phase-Resolved Polarimetry
• Analysis of a Century's Worth of AR Scorpii Photometry from DASCH and ASAS-SN
• An X-ray study for white dwarf binary AR Scorpii
• On the Polarized Nonthermal Emission from AR Scorpii
• Observations of AR Sco with $Chandra$ and $AstroSat$ Soft X-ray Telescope
• Modelling the polarisation signatures detected from the first white dwarf pulsar AR Sco