论文标题
在球状群集NGC 5024和NGC 5053中搜索潮流的RR Lyrae
A Search for Extra-Tidal RR Lyrae in the Globular Cluster NGC 5024 and NGC 5053
论文作者
论文摘要
最近，Kundu等人（2019年）报道说，球状簇NGC 5024（M53）具有五个潮汐外RR Lyrae。实际上，他们中的四个是附近球状群集NGC 5053的知名成员。剩余的潮气外RR Lyrae的状态取决于NGC 5024的潮汐半径。我们还搜索了在$ \ sim8 $ \ dg $^$^$^2 $ compol coply compoll compul compolar compul compul compul compul compul compul compul compul clusters clusters of lyrae的潮汐半径。这包括搜索区域内的其他已知RR Lyre，以及RR Lyre的幅度和颜色的预期范围内（在每个球状簇的潮汐半径的2/3截止范围内），如果它们是tielae rr thyae cantings for NGC 5024或ngc 5053，则应将其称为“大潮汐”）。颜色标记图，没有一个已知的RR Lyre属于任何一个球状簇的潮汐外RR Lyrae。在恒星满足RR Lyre的幅度和颜色范围的情况下，从Zwicky瞬态设施中获取的时间序列数据的分析不会揭示周期性，这表明这些恒星都不是RR Lyrae。我们得出的结论是，我们的搜索区域内没有与NGC 5024或NGC 5053相关的潮气外RR Lyrae。
Recently, Kundu et al (2019) reported that the globular cluster NGC 5024 (M53) possesses five extra-tidal RR Lyrae. In fact, four of them were instead known members of a nearby globular cluster NGC 5053. The status of the remaining extra-tidal RR Lyrae is controversial depending on the adopted tidal radius of NGC 5024. We have also searched for additional extra-tidal RR Lyrae within an area of $\sim8$~deg$^2$ covering both globular clusters. This includes other known RR Lyrae within the search area, as well as stars that fall within the expected range of magnitudes and colors for RR Lyrae (and yet outside the cutoff of 2/3 of the tidal radii of each globular clusters for something to be called "extra-tidal") if they were extra-tidal RR Lyrae candidates for NGC 5024 or NGC 5053. Based on the the proper motion information and their locations on the color-magnitude diagram, none of the known RR Lyrae belong to the extra-tidal RR Lyrae of either globular clusters. In the cases where the stars satisfied the magnitude and color ranges of RR Lyrae, analysis of time series data taken from the Zwicky Transient Facility do not reveal periodicities, suggesting that none of these stars are RR Lyrae. We conclude that there are no extra-tidal RR Lyrae associated with either NGC 5024 or NGC 5053 located within our search area.
