AM CVn star

AM CVn star

[162 ¦ā¦em ¦sē¦vē′en ‚stär]
(astronomy)
A binary system consisting of two orbiting white dwarf stars which fill their respective Roche lobes, exchange mass at the point of contact, and vary in brightness due to eclipses of one white dwarf by the other.
References in periodicals archive ?
An AM CVn star, or AM Canum Venaticorum star, is a type of cataclysmic variable star.
AM CVn stars differ from most other cataclysmic variables (CVs) in the lack of hydrogen lines from their spectra.
AM CVn stars with a white-dwarf donor can be formed when a binary consisting of a white dwarf and a low-mass giant evolve through a common-envelope (CE) phase.
AM CVn stars with a helium-star donor are formed in a similar way, but in this case the giant that causes the common envelope is more massive and produces a helium star rather than a second white dwarf.
The observed rebrightening episodes are similar to those seen during the 2003 June outburst of the AM CVn star V803 Cen.
The AM CVn stars are a class of cataclysmic variables comprising two interacting white dwarfs.
Very few confirmed AM CVn stars are known: only about two dozen are suspected at the time of writing.
Rather few AM CVn stars are known and the characteristics of the outbursting systems are not well studied.
AM CVn stars also hold great interest as mass transfer in these systems is believed to be driven by gravitational radiation.