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Related papers: Resynchronization of the Asynchronous Polar CD Ind

200 papers

There have been relatively few published long-duration, uninterrupted light curves of magnetic cataclysmic variable stars in which the accreting white dwarf's rotational frequency is slightly desynchronized from the binary orbital frequency…

Intermediate polars with known rates of spin period changes are not numerous because such tasks require measurements performed for a long time. To measure a spin period change, MU Cam is a good candidate because it has a spin oscillation…

Solar and Stellar Astrophysics · Physics 2016-09-28 V. P. Kozhevnikov

V1432 Aql is currently considered to be an asynchronous AM Her type system, with an orbital period of 12116.3 s and a spin period of 12150 s. I present an alternative model in which V1432 Aql is an intermediate polar with disk overflow or…

Astrophysics · Physics 2009-10-30 Koji Mukai

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

SW Sextantis systems are nova-like cataclysmic variables that have unusual spectroscopic properties, which are thought to be caused by an accretion geometry having part of the mass flux trajectory out of the orbital plane. Accretion onto a…

We present the results of near continuous TESS optical observations of the asynchronous polar CD Ind (RX J2115-5840). The 27.9 d long light curve, with 2 min resolution, reveals remarkable changes in the magnetic accretion geometry of the…

Solar and Stellar Astrophysics · Physics 2019-04-17 Pasi Hakala , Gavin Ramsay , Stephen B. Potter , Andrew Beardmore , David A. H. Buckley , Graham Wynn

We report the identification of the cataclysmic variable 1RXSJ062518.2+733433 as an intermediate polar. The orbital period of the system is determined to be 283.0+-2 min from the radial velocity variation of Halpha, measured in an extensive…

Astrophysics · Physics 2009-11-07 S. Araujo-Betancor , B. T. Gaensicke , H. -J. Hagen , P. Rodriguez-Gil , D. Engels

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

We report the discovery of an isolated white dwarf with a spin period of 70 s. We obtained high speed photometry of three ultramassive white dwarfs within 100 pc, and discovered significant variability in one. SDSS J221141.80+113604.4 is a…

Solar and Stellar Astrophysics · Physics 2021-12-15 Mukremin Kilic , Alekzander Kosakowski , Adam G. Moss , P. Bergeron , Annamarie A. Conly

The merger of close double white dwarfs (CDWDs) is one of the favourite evolutionary channels for producing Type Ia supernovae (SN Ia). Unfortunately, current theories of the evolution and formation of CDWDs are still poorly constrained and…

Solar and Stellar Astrophysics · Physics 2017-01-18 A. Rebassa-Mansergas , S. G. Parsons , E. Garcia-Berro , B. T. Gaensicke , M. R. Schreiber , M. Rybicka , D. Koester

We have identified a new intermediate polar, HS 0943+1404, as part of our ongoing search for cataclysmic variables in the Hamburg Quasar Survey. The orbital and white dwarf spin periods determined from time-resolved photometry and…

We present the results of photometric CCD observations of the magnetic cataclysmic variable V405 Aurigae (RX J0558.0+5353 = 1RXS J055800.7+535358) obtained using different instruments. We analysed variability of the spin period of the white…

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

A period analysis of CCD unfiltered photometry of V4745 Sgr (Nova Sgr 2003 #1) performed during 23 nights in the years 2003 - 2005 is presented. The photometric data are modulated with a period of 0.20782 +- 0.00003 d ($4.98768 +- 0.00072…

Astrophysics · Physics 2009-11-11 Andrej Dobrotka , Alon Retter , Alex Liu

Context: The object HS 0922+1333 was visited briefly in 2002 in a mini survey of low accretion rate polars (LARPs) in order to test if they undergo high luminosity states similar to ordinary polars. On the basis of that short observation…

Astrophysics · Physics 2009-11-13 G. H. Tovmassian , S. V. Zharikov

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

Accreting magnetic white dwarfs offer an opportunity to understand the interplay between spin-up and spin-down torques in binary systems. Monitoring of the white dwarf spin may reveal whether the white dwarf spin is currently in a state of…

Light curves of the Z Cam type dwarf nova AT Cnc observed during standstill in 2016 and 2018 are analyzed. On the time scale of hours, previous reports on periodicities, in particular the presence of negative superhumps, could not be…

We report the results of a twenty-eight-month photometric campaign studying V1432 Aql, the only known eclipsing, asynchronous polar. Our data show that both the residual eclipse flux and eclipse O-C timings vary strongly as a function of…

A modulation in the V-band with period 527.84+/-1.81 sec and amplitude 0.023 magnitude, attributable to the spin of the magnetic white dwarf primary star, has been detected in 7.5 hours of V-band CCD photometry data recorded during the…

Astrophysics · Physics 2007-05-23 David Boyd