The transfer of gas between stars in a binary system. The component that is losing material may have evolved to fill its Roche lobe (in which case the system is a semidetached binary), or it may be the source of a strong stellar wind. The component accreting material does so either directly from the stellar wind or a stream of gas, or indirectly through an accretion disk. The transferred gas is generally hydrogen-rich because it originates in the outer layers of the donor star.
Subjects: Astronomy and Astrophysics — Chemistry.