We investigate orbital period changes of two deep, low mass ratio（DLMR） overcontact W UMa-type binaries, FG Hya and GR Vir. It is found that the orbital period of FG Hya shows a cyclic change with a period of Pmod= ...We investigate orbital period changes of two deep, low mass ratio（DLMR） overcontact W UMa-type binaries, FG Hya and GR Vir. It is found that the orbital period of FG Hya shows a cyclic change with a period of Pmod= 54.44 yr. The cyclic oscillation may be due to a third body in an eccentric orbit, while the orbital period of GR Vir shows a periodic variation with a period of Pmod= 28.56 yr and an amplitude of A = 0.0352 d. The periodic variation of GR Vir can be interpreted as a result of either the light-time effect of an unseen third body or the magnetic activity cycle.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.11703020)Joint Research Funds in Astronomy(U1531108,U1731106 and U1731110)under cooperative agreement between the National Natural Science Foundation of China and Chinese Academy of Sciences
文摘We investigate orbital period changes of two deep, low mass ratio（DLMR） overcontact W UMa-type binaries, FG Hya and GR Vir. It is found that the orbital period of FG Hya shows a cyclic change with a period of Pmod= 54.44 yr. The cyclic oscillation may be due to a third body in an eccentric orbit, while the orbital period of GR Vir shows a periodic variation with a period of Pmod= 28.56 yr and an amplitude of A = 0.0352 d. The periodic variation of GR Vir can be interpreted as a result of either the light-time effect of an unseen third body or the magnetic activity cycle.
