收集了近相接双星BF Vir 的光极小时刻,并对其轨道周期进行分析.结果表明该星的轨道周期在长期减小的同时也含有30 年的周期性变化.对引起轨道周期变化的各种物理机制的分析研究表明:一个质量为0 .281 M⊙、绕公共质心的轨道半径为10 .2...收集了近相接双星BF Vir 的光极小时刻,并对其轨道周期进行分析.结果表明该星的轨道周期在长期减小的同时也含有30 年的周期性变化.对引起轨道周期变化的各种物理机制的分析研究表明:一个质量为0 .281 M⊙、绕公共质心的轨道半径为10 .2 AU 的第3天体的存在能对轨道周期的周期性变化成份作出解释,如果轨道周期的周期性变化成份是由于次子星的周期性磁活动引起,那么系统总光度就应该有振幅0 .097 L⊙的周期性变化,且其变化周期与轨道周期变化的周期相同;轨道周期的长期减小成份可能是由于该系统质量和角动量损失引起.BF Vir 是一个短周期的近相接双星系统,通过长期的质量和角动量损失它将可能会演化成一个A 次型的相接双星.展开更多
1 Introduction The explanation of the light curve of W UMa binary depends on the process of energy transfer. Recently, for this sort of binary, a lot of polarizations have been done to find out that many systems have ...1 Introduction The explanation of the light curve of W UMa binary depends on the process of energy transfer. Recently, for this sort of binary, a lot of polarizations have been done to find out that many systems have their intrinsic polarizations whose Stockes parameters change with their orbital phase. It has been estimated that there exsits a magnetic field about 20 Gauss with EXOSAT, VLA simultaneous observations of XY Leo and VW Cep. So an MHD model for energy transfer in contact binary is suggested here and some important observational facts are explained.展开更多
文摘收集了近相接双星BF Vir 的光极小时刻,并对其轨道周期进行分析.结果表明该星的轨道周期在长期减小的同时也含有30 年的周期性变化.对引起轨道周期变化的各种物理机制的分析研究表明:一个质量为0 .281 M⊙、绕公共质心的轨道半径为10 .2 AU 的第3天体的存在能对轨道周期的周期性变化成份作出解释,如果轨道周期的周期性变化成份是由于次子星的周期性磁活动引起,那么系统总光度就应该有振幅0 .097 L⊙的周期性变化,且其变化周期与轨道周期变化的周期相同;轨道周期的长期减小成份可能是由于该系统质量和角动量损失引起.BF Vir 是一个短周期的近相接双星系统,通过长期的质量和角动量损失它将可能会演化成一个A 次型的相接双星.
基金Present address: Center for Astrophysics, University of Science and Technology of China. Hefei 230026, PRC
文摘1 Introduction The explanation of the light curve of W UMa binary depends on the process of energy transfer. Recently, for this sort of binary, a lot of polarizations have been done to find out that many systems have their intrinsic polarizations whose Stockes parameters change with their orbital phase. It has been estimated that there exsits a magnetic field about 20 Gauss with EXOSAT, VLA simultaneous observations of XY Leo and VW Cep. So an MHD model for energy transfer in contact binary is suggested here and some important observational facts are explained.