We perform numerical simulations to investigate tidal evolution of two single-planet systems, that is, WASP-50 and GJ 1214 and a two-planet system CoRoT-7. The results of orbital evolution show that tidal decay and ci...We perform numerical simulations to investigate tidal evolution of two single-planet systems, that is, WASP-50 and GJ 1214 and a two-planet system CoRoT-7. The results of orbital evolution show that tidal decay and circularization may play a significant role in shaping their final orbits, which is related to the initial orbital data in the simulations. For GJ 1214 system, different cases of initial eccentricity are also considered as only an upper limit of its eccentricity （0.27） is shown, and the outcome suggests a possible maximum initial eccentricity （0.4） in the adopted dynamical model. Moreover, additional runs with alternative values of dissipation factor Q＇I are carried out to explore tidal evolution for GJ 1214b, and these results further indicate that the real Q＇1 of GJ 1214b may be much larger than its typical value, which may reasonably suggest that GJ 1214b bears a present-day larger eccentricity, undergoing tidal circularization at a slow rate. For the CoRoT-7 system, tidal forces make two planets migrating towards their host star as well as producing tidal circularization, and in this process tidal effects and mutual gravitational interactions are coupled with each other. Various scenarios of the initial eccentricity of the outer planet have also been done to investigate final planetary configuration. Tidal decay arising from stellar tides may still work for each system as the eccentricity decreases to zero, and this is in association with the remaining lifetime of each planet used to predict its future.展开更多
We have compiled a list of all planet host star candidates reported in the literature,which are likely to be cluster members,and we checked their memberships by the spatial location,radial velocity,proper motion and p...We have compiled a list of all planet host star candidates reported in the literature,which are likely to be cluster members,and we checked their memberships by the spatial location,radial velocity,proper motion and photometric criteria.We found that only six stars,BD-13 2130,HD 28305,Kepler-66,Kepler-67,Pr0201 and Pr0211,are planet orbiting stars in open clusters to date.Two stars,HD 70573 and HD 89744,belong to moving groups and one star,TYC 8975-2606-1,may not be a planet host star,while three stars,HD 16175,HD 46375 and HD 108874 are not members of open clusters.We note that all these six planetary systems in the stellar cluster environment are younger than^1 Gyr,which might indicate that the planetary system in open cluster can not survive for a long time,and we speculate that close stellar encounters between member stars in open cluster can potentially destroy,or at least strongly affect,the presence of planetary systems.展开更多
基金supported by the National Natural Science Foundation of China (Grant No.10973044,10833001)the Natural Science Foundation of Jiangsu Province(Grant No.BK20093411)the Foundation of Minor Planets of the Purple Mountain Observatory
文摘We perform numerical simulations to investigate tidal evolution of two single-planet systems, that is, WASP-50 and GJ 1214 and a two-planet system CoRoT-7. The results of orbital evolution show that tidal decay and circularization may play a significant role in shaping their final orbits, which is related to the initial orbital data in the simulations. For GJ 1214 system, different cases of initial eccentricity are also considered as only an upper limit of its eccentricity （0.27） is shown, and the outcome suggests a possible maximum initial eccentricity （0.4） in the adopted dynamical model. Moreover, additional runs with alternative values of dissipation factor Q＇I are carried out to explore tidal evolution for GJ 1214b, and these results further indicate that the real Q＇1 of GJ 1214b may be much larger than its typical value, which may reasonably suggest that GJ 1214b bears a present-day larger eccentricity, undergoing tidal circularization at a slow rate. For the CoRoT-7 system, tidal forces make two planets migrating towards their host star as well as producing tidal circularization, and in this process tidal effects and mutual gravitational interactions are coupled with each other. Various scenarios of the initial eccentricity of the outer planet have also been done to investigate final planetary configuration. Tidal decay arising from stellar tides may still work for each system as the eccentricity decreases to zero, and this is in association with the remaining lifetime of each planet used to predict its future.
基金supported by the National Natural Science Foundation of China(Grant Nos.11390371,11233004 and 11222326)the National Key Basic Research Program of China(Grant No.2014CB845703)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB01020300)
文摘We have compiled a list of all planet host star candidates reported in the literature,which are likely to be cluster members,and we checked their memberships by the spatial location,radial velocity,proper motion and photometric criteria.We found that only six stars,BD-13 2130,HD 28305,Kepler-66,Kepler-67,Pr0201 and Pr0211,are planet orbiting stars in open clusters to date.Two stars,HD 70573 and HD 89744,belong to moving groups and one star,TYC 8975-2606-1,may not be a planet host star,while three stars,HD 16175,HD 46375 and HD 108874 are not members of open clusters.We note that all these six planetary systems in the stellar cluster environment are younger than^1 Gyr,which might indicate that the planetary system in open cluster can not survive for a long time,and we speculate that close stellar encounters between member stars in open cluster can potentially destroy,or at least strongly affect,the presence of planetary systems.
