# Stellar streams around the Magellanic Clouds in 4D

**Authors:** Camila Navarrete, Vasily Belokurov, Márcio Catelan, Prashin Jethwa, Sergey E. Koposov, Julio A. Carballo-Bello, Paula Jofré, Denis Erkal, Sonia Duffau, Jesús M. Corral-Santana  
**arXiv:** [1811.11730](https://arxiv.org/abs/1811.11730)  
**Date:** 2018-11-28  
**Summary page:** https://www.summarizepaper.com/en/paper/1811.11730v1/

## Key points

- Study used spectroscopic follow-up program to investigate stellar stream candidates in LMC outskirts
- Medium-resolution spectra analyzed using FORS2 (VLT) to determine velocities, metallicities, and classify stars
- Sample divided between Magellanic Clouds and Galactic foreground through 4-D phase-space analysis
- Kinematic confirmation achieved for two out of four stream candidates
- Distribution of Magellanic stars in phase-space aligned with expected velocity gradients for LMC halo
- LMC's halo may be larger than previously thought, debris dispersed across significant distances
- Kinematic evidence suggests many stars originated from Small Magellanic Cloud
- Insights into dynamics and composition of stellar streams around Magellanic Clouds provided
- Research contributes to understanding galactic interactions and star formation processes within these regions

## Summary

A recent study utilized a spectroscopic follow-up program to investigate four newly identified stellar stream candidates in the outskirts of the Large Magellanic Cloud (LMC). By analyzing medium-resolution spectra using FORS2 (VLT), researchers were able to determine line-of-sight velocities, estimate stellar metallicities, and classify stars as Blue Horizontal Branch (BHB) or Blue Straggler (BS). Approximately half of the sample was attributed to the Magellanic Clouds through 4-D phase-space analysis, while the rest was identified as part of the Galactic foreground. Kinematic confirmation was achieved for only two out of the four stream candidates. Despite challenges in estimating Milky Way contamination levels, the distribution of Magellanic stars in phase-space aligned with expected velocity gradients for the LMC halo, extending up to 33 degrees or 29 kpc from its center. These findings suggest that the LMC's halo may be larger than previously thought and debris could be dispersed across significant distances from its center. Furthermore, kinematic evidence indicated that many analyzed stars likely originated from the Small Magellanic Cloud. This comprehensive analysis provides valuable insights into the dynamics and composition of stellar streams around the Magellanic Clouds and sheds light on their extended halos and potential connections to neighboring galaxies. Overall, this research contributes to our understanding of galactic interactions and star formation processes within these cosmologically significant regions.