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Related papers: A Model of White Dwarf Pulsar AR Scorpii

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The variable star 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 hr orbit with a more massive white…

High Energy Astrophysical Phenomena · Physics 2017-01-26 D. A. H. Buckley , P. J. Meintjes , S. B. Potter , T. R. Marsh , B. T Gänsicke

AR Scorpii, the so called white dwarf pulsar, contains a rapidly rotating magnetic white dwarf (WD; Pspin = 117.0564 s) interacting with a cool, red dwarf (RD) companion in a 3.56 hour orbit. It is a strong radio source with an inverted…

Solar and Stellar Astrophysics · Physics 2025-05-13 Paul E. Barrett , Mark A. Gurwell

Radio pulsating white dwarf (WD) systems, known as WD pulsars, are non-accreting binary systems where the rapidly spinning WD interacts with a low-mass companion producing pulsed non-thermal emission that can be observed across the entire…

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 pulsation every 1.97 minutes. Over the course of two…

Solar and Stellar Astrophysics · Physics 2018-09-19 Robert A. Stiller , Colin Littlefield , Peter Garnavich , Charlotte Wood , Franz-Josef Hambsch , Gordon Myers

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 some polars during quiescence. Such emission is…

Solar and Stellar Astrophysics · Physics 2019-02-20 Peter Garnavich , Colin Littlefield , Stella Kafka , Mark Kennedy , Paul Callanan , Dinshaw Balsara , Maxim Lyutikov

Marsh et al. (2016) have recently reported the discovery of a radio-pulsing white dwarf in the cataclysmic variable AR Sco. The period of pulsations which are also seen in the optical and UV is about 117 seconds. High intensity of pulsing…

High Energy Astrophysical Phenomena · Physics 2016-12-26 N. G. Beskrovnaya , N. R. Ikhsanov

White dwarfs are compact stars, similar in size to Earth but ~200,000 times more massive. Isolated white dwarfs emit most of their power from ultraviolet to near-infrared wavelengths, but when in close orbits with less dense stars, white…

AR Scorpii (AR Sco) is the only radio-pulsing white dwarf known to date. It shows a broad-band spectrum extending from radio to X-rays whose luminosity cannot be explained by thermal emission from the system components alone, and is instead…

AR~Scorpii is an intermediate polar system composed of a magnetic white dwarf (WD) and an M-type star, and shows non-thermal, pulsed, and highly linearly polarized emission. The radio/optical emission modulates with the WD's spin and show…

High Energy Astrophysical Phenomena · Physics 2017-12-27 J. Takata , H. Yang , K. S. Cheng

The binary system AR Scorpii hosts an M-type main sequence cool star orbiting around a magnetic white dwarf in the Milky Way Galaxy. The broadband non-thermal emission over radio, optical and X-ray wavebands observed from AR Scorpii…

High Energy Astrophysical Phenomena · Physics 2021-05-12 K. K. Singh , P. J. Meintjes , K. K. Yadav

White dwarf stars are the most common stellar fossils. When in binaries, they make up the dominant form of compact object binary within the Galaxy and can offer insight into different aspects of binary formation and evolution. One of the…

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 dwarf with a spin period of 1.95 min. Optical…

High Energy Astrophysical Phenomena · Physics 2019-07-03 L. du Plessis , Z. Wadiasingh , C. Venter , A. K. Harding , S. Chandra , P. J. Meintjies

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…

High Energy Astrophysical Phenomena · Physics 2018-05-16 Stephen B. Potter , David A. H. Buckley

AR Scorpii (AR Sco) is a binary star system containing the only known white dwarf (WD) pulsar. Previously reported photometric datasets only provide coverage back to 2005, but we extend the observational baseline for AR Sco back to the…

Solar and Stellar Astrophysics · Physics 2019-09-13 Erik Peterson , Colin Littlefield , Peter Garnavich

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 in detail, in order to constrain its origin and…

Solar and Stellar Astrophysics · Physics 2018-03-28 E. R. Stanway , T. R. Marsh , P. Chote , B. T. Gaensicke , D. Steeghs , P. J. Wheatley

We study linear polarization of optical emission from white dwarf (WD) binary system AR~Scorpii. The optical emission from this binary is modulating with the beat frequency of the system, and it is highly polarized, with the degree of the…

High Energy Astrophysical Phenomena · Physics 2019-05-01 J. Takata , K. S. Cheng

We report a study of the X-ray emission from the white dwarf/M-type star binary system AR Scorpii using archival data taken in 2016-2020. It has been known that the X-ray emission is dominated by the optically thin thermal plasma emission,…

High Energy Astrophysical Phenomena · Physics 2021-02-17 J. Takata , X. F. Wang , H. H. Wang , L. C. -C. Lin , C. -P. Hu , K. L. Li , A. K. H. Kong

Analysis of AR Sco optical light curves spanning nine years show a secular change in the relative amplitudes of the beat pulse pairs generated by the two magnetic poles of its rotating white dwarf. Recent photometry now shows that the…

We present detailed optical photo-polarimetric observations of the recently-discovered white dwarf pulsar AR Scorpii. Our extensive dataset reveals that the polarized emission is remarkably stable and repeatable with spin, beat and orbital…

High Energy Astrophysical Phenomena · Physics 2018-09-12 Stephen B. Potter , David A. H. Buckley

We analyze rapid-cadence, multiwavelength photometry of AR Scorpii from three observatories, covering five observing seasons. We measure the arrival times of the system's beat pulses and use them to compute an updated ephemeris. The white…

Solar and Stellar Astrophysics · Physics 2020-07-31 Yadira Gaibor , Peter Garnavich , Colin Littlefield , Stephen B. Potter , David A. H. Buckley
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