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Related papers: Accretion Stream Mapping of HU Aquarii

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We present a new mapping algorithm, the Accretion Stream Mapping, which uses the complete emission-line light curve to derive spatially resolved intensity distributions along the stream on a surface created as a duodecadon shaped tube. We…

Astrophysics · Physics 2007-05-23 Sonja Vrielmann , Axel D. Schwope

We present phase-resolved spectroscopy of the bright, eclipsing polar HU Aqr obtained with high time (~30sec) and spectral (1.6 A) resolution when the system was in a high accretion state. The trailed spectrograms reveal clearly the…

Astrophysics · Physics 2007-05-23 Axel D. Schwope , Karl-Heinz Mantel , Keith Horne

We present a new method to map the surface brightness of the accretion streams in AM Herculis systems from observed light curves. Extensive tests of the algorithm show that it reliably reproduces the intensity distribution of the stream for…

Astrophysics · Physics 2007-05-23 J. Kube , B. T. Gaensicke , K. Beuermann

We apply our technique for indirect imaging of the accretion stream to UBVR eclipse profiles of HU Aqr obtained when the system was in a high state. We perform model fits to the eclipses using two geometries: one where the stream accretes…

Astrophysics · Physics 2007-05-23 M K Harrop-Allin , Mark Cropper , P Hakala , C Hellier , T Ramseyer

We apply a new method of eclipse mapping to the light curves of eclipsing polars. The technique aims to locate the bright emission associated with the accretion stream, using a technique that makes the fewest prior assumptions about the…

Astrophysics · Physics 2007-05-23 C. M. Bridge , Pasi Hakala , Mark Cropper , Gavin Ramsay

We present a magnetic stripping model for AM Her type objects. Our model is based on an equilibrium condition between ram pressure and magnetic pressure in a stiff dipolar magnetic field. We investigate the detailed geometry of the…

Astrophysics · Physics 2009-10-31 Claus Heerlein , Keith Horne , Axel D. Schwope

We apply an eclipse mapping technique to observations of the eclipsing magnetic cataclysmic variable HU Aqr. The observations were made with the S-Cam2 Superconducting Tunnel Junction detector at the WHT in October 2000, providing high…

Time-resolved spectroscopy of the novalike variable UU Aquarii is analyzed with eclipse mapping techniques to produce spatially resolved spectra of its accretion disc and gas stream as a function of distance from disc centre in the range…

Astrophysics · Physics 2007-05-23 R. Baptista , C. Silveira , J. E. Steiner , K. Horne

We have developed a 3D computer model of polars which includes the accretion stream, the accretion column, the secondary star, and the white dwarf. Each component is represented by a fine grid of surface elements. With brightness values…

Astrophysics · Physics 2007-05-23 Jens Kube , Boris T. Gaensicke , Klaus Beuermann

We report on XMM-Newton and NuSTAR X-ray observations of the prototypical polar, AM Herculis, supported by ground-based photometry and spectroscopy, all obtained in high accretion states. In 2005, AM Herculis was in its regular mode of…

Solar and Stellar Astrophysics · Physics 2020-10-14 A. D. Schwope , H. Worpel , I. Traulsen , D. Sablowski

We apply an eclipse mapping technique using `genetically modified fire-flies' to the eclipse light curves of HU Aqr and EP Dra. The technique makes as few assumptions as possible about the location of accretion stream material, allowing the…

Astrophysics · Physics 2009-11-10 C. M. Bridge , Pasi Hakala , Mark Cropper , Gavin Ramsay

Time-resolved spectroscopy of the novalike variable UU Aquarii is analyzed with eclipse mapping techniques to produce spatially resolved spectra of its accretion disc and gas stream as a function of distance from disc centre in the range…

Astrophysics · Physics 2009-10-31 Raymundo Baptista , C. Silveira , J. E. Steiner , Keith Horne

A hydrodynamic formulation for accretion flow channeled by a dipolar magnetic field is constructed using a curvi-linear coordinate system natural to the field structure. We solve the hydrodynamic equations and determine the velocity,…

Astrophysics · Physics 2007-05-23 J. B. G. Canalle , Kinwah Wu , Mark Cropper , Gavin Ramsay , Curtis Saxton

We review the main observational characteristics of AM Herculis stars (polars) at X-ray, EUV, UV, IR and optical wavelengths. Particular emphasis is given to multi-epoch, multi-wavelength observations of the eclipsing polar HU Aqr (RX…

We have solved the one-dimensional stationary two-fluid hydrodynamic equations for post-shock flows on accreting magnetic white dwarfs simultaneous with the fully frequency and angle-dependent radiative transfer for cyclotron radiation and…

Astrophysics · Physics 2009-11-06 A. Fischer , K. Beuermann

We present the first high time resolution light curves for six eclipses of the magnetic cataclysmic variable EP Dra, taken using the superconducting tunnel junction imager S-Cam2. The system shows a varying eclipse profile between…

We want to study the temporal and spectral behaviour of HU Aqr in the X-ray domain during different accretion states. We obtained spectra and light curves from four different XMM-Newton pointings covering intermediate and low states. The…

Solar and Stellar Astrophysics · Physics 2009-11-13 R. Schwarz , A. D. Schwope , J. Vogel , V. S. Dhillon , T. R. Marsh , C. Copperwheat , S. P. Littlefair , G. Kanbach

We have developed a model of the high-energy accretion region for magnetic cataclysmic variables and applied it to {\it Extreme Ultraviolet Explorer} observations of 10 AM Herculis type systems. The major features of the EUV light curves…

Astrophysics · Physics 2009-10-30 Martin M. Sirk , Steve B. Howell

We performed 3D MHD calculations of stream accretion in cataclysmic variable stars for which the white dwarf primary star possesses a strong and complex magnetic field. These calculations are motivated by observations of polars; cataclysmic…

High Energy Astrophysical Phenomena · Physics 2012-10-16 A. G. Zhilkin , D. V. Bisikalo , P. A. Mason

We present phase-resolved spectroscopy of AM Herculis obtained with the HST/GHRS when the system was in a high state. The ultraviolet light curve shows a quasi-sinusoidal modulation, which can be explained by a hot spot on the rotating…

Astrophysics · Physics 2007-05-23 B. T. Gaensicke , D. W. Hoard , K. Beuermann , E. M. Sion , P. Szkody
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