Polarimetric evidence of a white dwarf pulsar in the binary system AR Scorpii

  title={Polarimetric evidence of a white dwarf pulsar in the binary system AR Scorpii},
  author={David A H Buckley and Petrus J. Meintjes and Stephen B Potter and Thomas R. Marsh and B. T. Gansicke},
  journal={Nature Astronomy},
The variable star AR Scorpii (AR Sco) was recently discovered to pulse in brightness every 1.97 min from ultraviolet wavelengths into the radio regime. The system is composed of a cool, low-mass star in a tight, 3.55-hour orbit with a more massive white dwarf. Here we report new optical observations of AR Sco that show strong linear polarization (up to 40%) that varies strongly and periodically on both the spin period of the white dwarf and the beat period between the spin and orbital period… Expand

Figures from this paper

Polarimetric Evidence of the First White Dwarf Pulsar: The Binary System AR Scorpii
The binary star AR Scorpii was recently discovered to exhibit high amplitude coherent variability across the electromagnetic spectrum (ultraviolet to radio) at two closely spaced ∼2 min periods,Expand
Modelling the polarisation signatures detected from the first white dwarf pulsar AR Sco.
Marsh et al. detected radio and optical pulsations from the binary system AR Scorpii (AR Sco). This system, with an orbital period of 3.56 h, is composed of a cool, low-mass star and a white dwarfExpand
VLA Radio Observations of AR Sco
AR Scorpii is unique amongst known white dwarf binaries in showing powerful pulsations extending to radio frequencies. Here we aim to investigate the multi-frequency radio emission of AR Sco inExpand
Driving the Beat: Time-resolved Spectra of the White Dwarf Pulsar AR Scorpii
We obtained high temporal resolution spectroscopy of the unusual binary system AR Sco covering nearly an orbit. The H$\alpha$ emission shows a complex line structure similar to that seen in someExpand
Properties of white dwarf in the binary system AR Scorpii and its observed features
Present Address Astrophysical Sciences Division, Bhabha Atomic Research Centre, Mumbai 400085, India The binary system AR Scorpii hosts an M-type main sequence cool star orbiting around a magneticExpand
High-time-resolution Photometry of AR Scorpii: Confirmation of the White Dwarf’s Spin-down
The unique binary AR Scorpii consists of an asynchronously rotating, magnetized white dwarf (WD) that interacts with its red-dwarf companion to produce a large-amplitude, highly coherent pulsationExpand
Towards the origin of the radio emission in AR Scorpii, the first radio-pulsing white dwarf binary
Context. The binary system AR Sco contains an M star and the only known radio-pulsing white dwarf. The system shows emission from radio to X-rays, likely dominated by synchrotron radiation. TheExpand
Results form the long-term Fermi-LAT observations of the white dwarf binary pulsar AR Scorpii
The discovery of the white dwarf binary system AR Scorpii (AR Sco) with its fascinating non-thermal dominated multi-frequency emission has sparked renewed interest in potential high energy gamma-rayExpand
AR Sco: A Precessing White Dwarf Synchronar?
The emission of the white dwarf–M dwarf binary AR Sco is driven by the rapid synchronization of its white dwarf, rather than by accretion. Synchronization requires a magnetic field ~100 Gauss at theExpand
Search for Gamma-ray emission in the White Dwarf pulsar of AR Scorpii
Detailed multi-frequency studies of the white dwarf pulsar AR Scorpii (AR Sco) revealed a Spectral Energy Distribution (SED) which predominantly shows features of nonthermal emission between theExpand


A Model of White Dwarf Pulsar AR Scorpii
A 3.56-hour white dwarf (WD) - M dwarf (MD) close binary system, AR Scorpii, was recently reported to show pulsating emission in radio, IR, optical, and UV, with a 1.97-minute period, which suggestsExpand
A radio-pulsing white dwarf binary star
The discovery is reported of a white dwarf/cool star binary that emits from X-ray to radio wavelengths and the spin-down power is an order of magnitude larger than that seen in electromagnetic radiation, which suggests that AR Sco is primarily spin-powered. Expand
We review the properties of the DQ Herculis stars: cataclysmic variables containting an accreting, magnetic, rapidly rotating white dwarf. These stars are characterized by strong X-ray emission,Expand
AR Sco: A Precessing White Dwarf Synchronar?
The emission of the white dwarf–M dwarf binary AR Sco is driven by the rapid synchronization of its white dwarf, rather than by accretion. Synchronization requires a magnetic field ~100 Gauss at theExpand
The X-ray luminosity of rotation-powered neutron stars
As a result of recent observations with ROSAT and ASCA the number of rotation-powered pulsars seen at X-ray energies has increased substantially. In this paper we review the phenomenology of theExpand
Synchronous rotation in magnetic X-ray binaries.
AM Herculis is thought to be a binary stellar system that contains an accreting magnetic degenerate dwarf whose rotation is synchronous with the orbital period. This synchronism is remarkable,Expand
Radio flares from AE Aquarii - A low-power analog to Cygnus X-37
The magnetic cataclysmic variable AE Aquarii has been observed at 1.5, 4.9, 15, and 22.5 GHz. The source shows temporal variations in the flux density, often with a flarelike morphology. The fluxExpand
Secondary star magnetic fields in close binaries
In this paper an attempt is made to use magnetic braking to constrain the surface polar field strengths of the secondary stars in close binaries with orbital periods between P orb ∼ 3 and 7 h. ByExpand
Optical polarization of the Crab pulsar: precision measurements and comparison to the radio emission
The linear polarization of the Crab pulsar and its close environment was derived from observations with the high-speed photopolarimeter Optical Pulsar TIMing Analyser at the 2.56-m Nordic OpticalExpand
On the spin modulated circular polarization from the intermediate polars NY Lup and IGR J15094–6649
We report on high-time-resolution, high-signal-to-noise ratio (S/N), photopolarimetry of the intermediate polars NY Lup and IGR J15094–6649. Our observations confirm the detection and colourExpand