This paper investigates the spin-up of a mass-accreting star in a close binary system passing through the first stage of mass exchange in the Hertzsprung gap. Inside an accreting star, angular momentum is carried by m...This paper investigates the spin-up of a mass-accreting star in a close binary system passing through the first stage of mass exchange in the Hertzsprung gap. Inside an accreting star, angular momentum is carried by meridional circulation and shear turbulence. The circulation carries part of the angular momentum of the accreted layers to the accretor's surface. The greater the rate of arrival of angular momentum in the accretor is, the greater this part. It is assumed that this part of the angular momentum can be removed by the disk further from the accretor. If the angular momentum in the matter entering the accretor is more than half the Keplerian value, then the angular momentum obtained by the accretor during mass exchange stage does not depend on the rate of arrival of angular momentum. The accretor may have the characteristics of a Be-star immediately after the end of mass exchange.展开更多
We investigate the exchange of mass in a binary system as a channel through which a Be star can receive a rapid rotation.The mass-transfer phase in a massive close binary system in the Hertzsprung-gap is accompanied b...We investigate the exchange of mass in a binary system as a channel through which a Be star can receive a rapid rotation.The mass-transfer phase in a massive close binary system in the Hertzsprung-gap is accompanied by the spinning up of the accreting component.We consider a case when the mass of the accreting component increases by 1.5 times.The component acquires mass and angular momentum while in a state of critical rotation.The angular momentum of the component increases by 50 times.Meridional circulation effectively transports angular momentum inside the component during the mass-transfer phase and during the thermal timescale after the end of the mass-transfer phase.As a result of mass transfer,the component acquires the rotation typical of classical Be stars.展开更多
The spinning-up of the accreting component in the process of conservative mass exchange is considered in binary systems—progenitors of systems consisting of a main sequence Be-star and an O-subdwarf.During the mass e...The spinning-up of the accreting component in the process of conservative mass exchange is considered in binary systems—progenitors of systems consisting of a main sequence Be-star and an O-subdwarf.During the mass exchange,the meridional circulation transfers 80%-85%of the angular momentum that entered the accretor together with the accreted matter to the accretor surface.This angular momentum is removed from the accretor by the disk.When the mass exchange finishes,the accretor has a rotation typical of classical Be-type stars.展开更多
基金supported by the Ministry of Science and EducationFEUZ-2023-0019。
文摘This paper investigates the spin-up of a mass-accreting star in a close binary system passing through the first stage of mass exchange in the Hertzsprung gap. Inside an accreting star, angular momentum is carried by meridional circulation and shear turbulence. The circulation carries part of the angular momentum of the accreted layers to the accretor's surface. The greater the rate of arrival of angular momentum in the accretor is, the greater this part. It is assumed that this part of the angular momentum can be removed by the disk further from the accretor. If the angular momentum in the matter entering the accretor is more than half the Keplerian value, then the angular momentum obtained by the accretor during mass exchange stage does not depend on the rate of arrival of angular momentum. The accretor may have the characteristics of a Be-star immediately after the end of mass exchange.
基金supported by the Ministry of Science and Education,FEUZ-2020-0030。
文摘We investigate the exchange of mass in a binary system as a channel through which a Be star can receive a rapid rotation.The mass-transfer phase in a massive close binary system in the Hertzsprung-gap is accompanied by the spinning up of the accreting component.We consider a case when the mass of the accreting component increases by 1.5 times.The component acquires mass and angular momentum while in a state of critical rotation.The angular momentum of the component increases by 50 times.Meridional circulation effectively transports angular momentum inside the component during the mass-transfer phase and during the thermal timescale after the end of the mass-transfer phase.As a result of mass transfer,the component acquires the rotation typical of classical Be stars.
基金supported by the Ministry of Science and Education,FEUZ-2020-0038。
文摘The spinning-up of the accreting component in the process of conservative mass exchange is considered in binary systems—progenitors of systems consisting of a main sequence Be-star and an O-subdwarf.During the mass exchange,the meridional circulation transfers 80%-85%of the angular momentum that entered the accretor together with the accreted matter to the accretor surface.This angular momentum is removed from the accretor by the disk.When the mass exchange finishes,the accretor has a rotation typical of classical Be-type stars.