# The substructures in the local stellar halo from Gaia and LAMOST

## TL;DR

This paper utilizes Gaia DR2 and LAMOST data to identify and analyze substructures in the local stellar halo, revealing both known and new streams that shed light on the Milky Way's accretion history.

## Contribution

The study detects four significant stellar halo substructures, including three newly identified streams, using combined kinematic and chemical data from Gaia and LAMOST.

## Key findings

- Identified 4 significant halo substructures, including 3 new streams.
- Confirmed the known N2 stream within the halo.
- Provided insights into the Milky Way's accretion history.

## Abstract

Based on the second Gaia data release (Gaia DR2) and spectroscopy from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) Data, we identified 20,089 halo stars kinematically and chemically. The halo streams in the solar neighborhood could be detected in the space of energy and angular momentum. We reshuffle the velocities of these stars to determine the significance of substructure. Finally, we identify 4 statistically significant substructures that are labeled GL-1 through 4. Among these substructures, GL-1 is previously known stream ("N2" stream) and the rest 3 substructures are new. These substructures may be the debris of dwarf galaxies accretion event, their dynamical and chemical information can help to understand the history of the Milky Way.