The outburst properties of AM CVn stars

نویسندگان

  • Iwona Kotko
  • Jean-Pierre Lasota
  • Guillaume Dubus
چکیده

We briefly summarize the observational properties of ultra-compact binaries called AM CVn stars. We analize their outbursts originating from the thermal-viscous instability in helium accretion disc. We present our preliminary results in applying the model of Dwarf Novae outbursts to helium discs. We can calculate models of outbursts of reasonable amplitude of 2 mag with a constant α parameter throughout the calculation. Setting the mass transfer rate close to its upper critical value produces model lightcurves that resemble short superoutbursts.

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تاریخ انتشار 2005