Binary interactions with high accretion rates onto main sequence stars
摘要
Energetic outflows from main sequence stars accreting mass at very high rates might account for the powering of some eruptive objects, such as merging main sequence stars, major eruptions of luminous blue variables, e.g., the Great Eruption of Eta Carinae, and other intermediate luminosity optical transients(ILOTs; red novae; red transients). These powerful outflows could potentially also supply the extra energy required in the common envelope process and in the grazing envelope evolution of binary systems. We propose that a massive outflow/jets mediated by magnetic fields might remove energy and angular momentum from the accretion disk to allow such high accretion rate flows. By examining the possible activity of the magnetic fields of accretion disks, we conclude that indeed main sequence stars might accrete mass at very high rates, up to≈10-2M⊙yr-1for solar type stars, and up toion≈1 M-⊙yr1for very massive stars. We speculate that magnetic fields amplified in such extreme condits might lead to the formation of massive bipolar outflows that can remove most of the disk’s energy and angular momentum. It is this energy and angular momentum removal that allows the very high mass accretion rate onto main sequence stars.