SDSS J 0926 + 3624 , the first eclipsing AM CVn star , as seen with ULTRACAM
نویسندگان
چکیده
We present light curves of SDSS J0926+3624, the first eclipsing AM CVn star, observed with the high-speed CCD camera ULTRACAM on the WHT. We find unusually that the accreting white dwarf is only partially eclipsed by its companion. Apart from this, the system shows the classic eclipse morphology displayed by eclipsing dwarf novae, namely the eclipse of a white dwarf and accretion disc followed by that of the bright spot where the mass transfer stream hits the disc. We are able to fit this well to find masses of the accretor and donor to be M 1 = 0.84 ± 0.05 M ⊙ and M 2 = 0.029 ± 0.02 M ⊙ respectively. The mass of the donor is significantly above its zero temperature value and it must possess significant thermal content.
منابع مشابه
Direct Detection of SDSS J0926+3624 Orbital Expansion with ARCONS
AM Canum Venaticorum (AM CVn) stars belong to a class of ultra-compact, short period binaries with spectra dominated largely by helium. SDSS J0926+3624 is of particular interest as it is the first observed eclipsing AM CVn system. We observed SDSS J0926+3624 with the Array Camera for Optical to Near-IR Spectrophotometry (ARCONS) at the Palomar 200” telescope. ARCONS uses a relatively new type o...
متن کاملSDSS J0926+3624: the shortest period eclipsing binary star
With orbital periods of the order of tens of minutes or less, the AM Canum Venaticorum stars are ultracompact, hydrogen-deficient binaries with the shortest periods of any binary subclass, and are expected to be among the strongest gravitational wave sources in the sky. To date, the only known eclipsing source of this type is the P = 28 min binary SDSS J0926+3624. We present multiband, high tim...
متن کاملSDSS J080449.49+161624.8: a peculiar AM CVn star from a colour-selected sample of candidates
We describe a spectroscopic survey designed to uncover an estimated ∼40 AM Canum Venaticorum (AM CVn) stars hiding in the photometric data base of the Sloan Digital Sky Survey. We have constructed a relatively small sample of about 1500 candidates based on a colour selection, which should contain the majority of all AM CVn binaries while remaining small enough that spectroscopic identification ...
متن کاملThe long-period AM CVn star SDSSJ155252.48+320150.9
The Sloan Digital Sky Survey has been instrumental in obtaining a homogeneous sample of the rare AM CVn stars: mass-transferring binary white dwarfs. As part of a campaign of spectroscopic follow-up on candidate AM CVn stars from the Sloan Digital Sky Survey, we have obtained time-resolved spectra of the g = 20.2 candidate SDSS J155252.48+320150.9 on the Very Large Telescope of the European Sou...
متن کاملThe AM CVn binary SDSSJ173047.59+554518.5
The AM Canum Venaticorum (AM CVn) binaries are a rare group of hydrogendeficient, ultra-short period, mass-transferring white dwarf binaries, and are possible progenitors of type Ia supernovae. We present time-resolved spectroscopy of the recently-discovered AM CVn binary SDSS J173047.59+554518.5. The average spectrum shows strong double-peaked helium emission lines, as well as a variety of met...
متن کامل