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Related papers: An X-ray study for white dwarf binary AR Scorpii

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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

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 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

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…

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

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

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 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

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…

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

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

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…

In this work, we have analyzed the $\gamma$-ray data in the energy range 100 MeV to 500 GeV from the \emph{Fermi}-Large Area Telescope (LAT) observations for the period August 4, 2008 to March 31, 2019. The $\gamma$-ray emission from AR…

High Energy Astrophysical Phenomena · Physics 2020-07-15 K. K. Singh , P. J. Meintjes , Q. Kaplan , F. A. Ramamonjisoa , S. Sahayanathan

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-ray emission from white dwarf pulsars. The…

High Energy Astrophysical Phenomena · Physics 2019-08-02 Q. Kaplan , P. J. Meintjes , K. K. Singh , H. J. van Heerden , F. A. Ramamonjisoa , I. P. van der Westhuizen

We report the analysis result of UV/X-ray emission from AR~Scorpii, which is an intermediate polar (IP) composed of a magnetic white dwarf and a M-type star, with the XMM-Newton data. The X-ray/UV emission clearly shows a large variation…

High Energy Astrophysical Phenomena · Physics 2018-02-14 J. Takata , C. -P. Hu , L. C. C. Lin , P. H. T. Tam , P. S. Pal , C. Y. Hui , A. K. H. Kong , K. S. Cheng

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 suggests the existence of a WD with a rotation…

High Energy Astrophysical Phenomena · Physics 2017-05-11 Jin-Jun Geng , Bing Zhang , Yong-Feng Huang

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

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

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

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…

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