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Related papers: The Helium-Rich Cataclysmic Variable ES Ceti

200 papers

We present the analysis of the spectroscopic observations of a newly discovered cataclysmic variable HS0551+7241. In 1995 the star's brightness dropped by Delta(B)~2.5 mag and HS0551+7241 entered a low state lasting for ~2 yr. The H-alpha,…

Astrophysics · Physics 2009-10-30 D. Dobrzycka , A. Dobrzycki , D. Engels , H. -J. Hagen

Using the Hopkins Ultraviolet Telescope (HUT), we have obtained 850-1850 angstrom spectra of the magnetic cataclysmic variable star AM Her in the high state. These observations provide high time resolution spectra of AM Her in the FUV and…

Astrophysics · Physics 2009-10-31 Bradford W. Greeley , William P. Blair , Knox S. Long , John C. Raymond

We present ULTRACAM photometry of ES Cet, an ultracompact binary with a 620s orbital period. The mass transfer in systems such as this one is thought to be driven by gravitational radiation, which causes the binary to evolve to longer…

Solar and Stellar Astrophysics · Physics 2015-05-27 C. M. Copperwheat , T. R. Marsh , V. S. Dhillon , S. P. Littlefair , P. A. Woudt , B. Warner , J. Patterson , D. Steeghs , J. Kemp , E. Armstrong , R. Rea

We report the discovery of 1RXH J082623.6-505741, a 10.4 hr orbital period compact binary. Modeling extensive optical photometry and spectroscopy reveals a $\sim 0.4 M_{\odot}$ K-type secondary transferring mass through a low-state…

Helium that accretes onto a Carbon/Oxygen white dwarf in the double white dwarf AM Canum Venaticorum (AM CVn) binaries undergoes unstable thermonuclear flashes when the orbital period is in the 3.5-25 minute range. At the shortest orbital…

Astrophysics · Physics 2009-11-13 Lars Bildsten , Ken J. Shen , Nevin N. Weinberg , Gijs Nelemans

We present high speed photometric observations of 20 faint cataclysmic variables, selected from the Sloan Digital Sky Survey and Catalina catalogues. Measurements are given of 15 new directly measured orbital periods, including four…

Solar and Stellar Astrophysics · Physics 2015-06-03 Patrick A. Woudt , Brian Warner , Deanne de Bude , Sally Macfarlane , Matthew P. E. Schurch , Ewald Zietsman

We present high-speed, three-colour photometry of the eclipsing cataclysmic variable SDSS J170213.26+322954.1 (hereafter SDSS J1702+3229). This system has an orbital period of 2.4 hours, placing it within the ``period gap'' for cataclysmic…

Astrophysics · Physics 2009-11-11 S. P. Littlefair , V. S. Dhillon , T. R. Marsh , B. T. Gaensicke

We present the first reliable determination of the orbital period of the recurrent nova V2487 Oph (Nova Oph 1998). We derived a value of $0.753 \pm 0.016$ d ($18.1 \pm 0.4$ h) from the radial velocity curve of the intense He II…

We report the discovery of one unique cataclysmic variable drawn from the Hamburg Quasar Survey, HS2331+3905. Follow-up observations obtained over three years unveiled a very unusual picture. The large amplitude 3.5 h radial velocity…

Perhaps the most extreme examples of "Active OB stars" are the subset of high-mass X-ray binaries -- consisting of an OB star plus compact companion -- that have recently been observed by Fermi and ground-based Cerenkov telescopes like HESS…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Stan Owocki , Atsuo Okazaki , Gustavo Romero

Continuing our work from Paper I (Southworth et al., 2006) we present medium-resolution spectroscopy and broad-band photometry of seven cataclysmic variables (CVs) discovered by the SDSS. For six of these objects we derive accurate orbital…

Although a large number of orbital periods of cataclysmic variable stars (CVs) have been measured, comparison of period and luminosity distributions with evolutionary theory is affected by strong selection effects. A test has been…

Astrophysics · Physics 2009-11-07 R. C. North , T. R. Marsh , U. Kolb , V. S. Dhillon , C. K. J. Moran

We present the results of a two and a half year optical photometric monitoring programme covering 16 AM CVn binaries using the Liverpool Telescope on La Palma. We detected outbursts in seven systems, one of which (SDSS J0129) was seen in…

Astrophysics of Galaxies · Physics 2015-05-30 Gavin Ramsay , Thomas Barclay , Danny Steeghs , Peter J. Wheatley , Pasi Hakala , Iwona Kotko , Simon Rosen

We present phase-resolved spectroscopy of the short period cataclysmic variable WZ Sge obtained with the Hubble Space Telescope. We were able to resolve the orbital motion of a number of absorption lines that likely probe the environment…

Astrophysics · Physics 2009-11-13 D. Steeghs , S. Howell , C. Knigge , B. Gaensicke , E. Sion , W. Welsh

We present the first time-resolved spectroscopic study of the cataclysmic variable DW Cancri. We have determined an orbital period of 86.10 +- 0.05 min, which places the system very close to the observed minimum period of hydrogen-rich…

Astrophysics · Physics 2009-11-10 P. Rodriguez-Gil , B. T. Gaensicke , S. Araujo-Betancor , J. Casares

Ultraviolet observations using the Solar Blind Channel on the Hubble Space Telescope provide light curves and low resolution spectra of three pulsating white dwarfs in the cataclysmic variables SDSS013132.39-090122.3,…

High time resolution spectroscopic observations of the ultra-compact helium dwarf nova 'SN 2003aw' in its quiescent state at V=20.5 reveal its orbital period at 2027.8 +/- 0.5 seconds or 33.80 minutes. Together with the photometric…

Astrophysics · Physics 2009-11-13 G. Roelofs , P. Groot , T. Marsh , D. Steeghs , G. Nelemans

We present far-ultraviolet (905 -- 1182 A), time-series spectroscopy of the eclipsing, novalike cataclysmic variable, UX UMa, acquired with FUSE. The time-averaged spectrum is complex and is dominated by overlapping spectral features. The…

Astrophysics · Physics 2009-11-07 C. S. Froning , K. S. Long , C. Knigge

Recent papers published in the last years contributed to resolve the enigma on the hypothetical Be nature of the hot pulsating star $\beta$ Cep. This star shows variable emission in the H$\alpha$ line, typical for Be stars, but its…

Astrophysics · Physics 2009-11-13 G. Catanzaro

We present HST spectroscopy for 45 cataclysmic variables (CVs), observed with HST/COS and HST/STIS. For 36 CVs, the white dwarf is recognisable through its broad Ly$\alpha$ absorption profile and we measure the white dwarf effective…