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arXiv · 2607.21934

Long Tidal Tails of NGC 5024 Hidden in LMS-1 and NGC 5053 Tidal Streams

Xianhao Ye·Yong Yang·Jingkun Zhao·Hao Tian·Yuqin Chen·Gang Zhao
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Abstract

We report the discovery of long tidal tails associated with the globular cluster (GC) NGC 5024. A modified matched filter applied to Gaia DR3 data reveals a broad stellar stream spanning $\alpha \approx 230^{\circ}-175^{\circ}$. The stellar stream overlaps on the sky with the LMS-1 and with the simulated stream of the GC NGC 5053, and all three share similar proper motions and metallicity. Our member candidates may therefore be a mixture of stars from NGC 5024, NGC 5053, and LMS-1. Nevertheless, the trailing tail extends roughly $20^{\circ}$ beyond the known LMS-1 stream. Furthermore, the radial velocity (RV) as a function of $\alpha$ is used to distinguish the genuine stream candidates of NGC 5024 from the streams of NGC 5053 and LMS-1. Among the sources in common with DESI (Dark Energy Spectroscopic Instrument) DR1, we found two distinct sequences in RV-$\alpha$ plane, corresponding to the stellar streams of NGC 5024 and NGC 5053 (or LMS-1), respectively. This constitutes the first strong evidence for the existence of extensive tidal tails around NGC 5024.

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Xianhao Ye, Yong Yang, Jingkun Zhao, Hao Tian, Yuqin Chen, Gang Zhao. 2026-07-24. Long Tidal Tails of NGC 5024 Hidden in LMS-1 and NGC 5053 Tidal Streams. https://arxiv.org/abs/2607.21934

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