The Formation of Subdwarf B Stars

摘要: We performed full binary evolution calculations and carried out population synthesis studies in order to investigate the formation of subdwarf B (sdB) stars via, channels stable Roche lobe overflow (RLOF), common envelope ejection helium white dwarf mergers. Our model is successful explanation observational properties sdB stars, e.g. we explained orbital period - minimum companion mass (log P M-comp) diagram, effective temperature surface gravity (T-eff log g) distribution, log(gtheta(4)) (theta = 5040/T-eff) function binary. fraction binaries with WD companions, birth rates, space number densities, etc. conclude that (a) first RLOF needs be more stabilized than commonly assumed, (b) not conservative, (c) very efficient.