期刊
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
卷 483, 期 2, 页码 1737-1743出版社
OXFORD UNIV PRESS
DOI: 10.1093/mnras/sty3239
关键词
proper motion; stars: variables: RR Lyrae; globular clusters: individual: NGC 3201, NGC 5024
资金
- Council of Scientific and Industrial Research, New Delhi
- BASAL Center for Astrophysics and Associated Technologies (CATA) [PFB-06]
- Ministry for the Economy, Development and Tourism, Programa Iniciativa Cientifica Milenio grant [IC120009]
- project Fondecyt [1170121]
- Indo-US Science and Technology Forum
We used extra-tidal RR Lyrae stars to study the dynamics of Galactic globular clusters and know how effects like dynamical friction and tidal disruption affect these clusters. The Gaia DR2 catalogue for RR Lyrae stars (Clementini et al. 2018) is used along with the proper motions and tidal radii data for the globular clusters compiled from literature. A sample of 56 Galactic globular clusters is analysed. Out of these 56 Galactic globular clusters, only 11 have extra-tidal RR Lyrae stars. However, only two clusters, namely, NGC 3201 and NGC 5024, have enough extra-tidal RR Lyrae stars to draw interesting conclusions. NGC 3201 has 13 extra-tidal RR Lyrae stars which are asymmetrically distributed around its centre with more number of stars in its trailing zone than its leading part. We conclude that these asymmetrical tidal tails are due to the combined effect of tidal disruption and the stripped debris from the cluster. On the other hand, NGC 5024 has five extra-tidal RR Lyrae stars, four of them are concentrated in a region which is at a distance of about three times the tidal radius from its centre. These may be the stars that are being ripped apart from the cluster due to tidal disruption. The presence of these extra-tidal RR Lyrae stars in the clusters can be an indication that more cluster stars are present outside their tidal radii which may be revealed by deep wide field colour-magnitude diagrams of the clusters.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据