The Nearest High-Velocity Stars Revealed by LAMOST Data Release 1

TL;DR

This paper reports the discovery of 28 candidate high-velocity stars within 3 kpc using LAMOST DR1 data, expanding the known sample and enabling better understanding of their origins and Galactic structure.

Contribution

It presents the first and largest sample of nearby high-velocity star candidates from LAMOST, covering a broader color range than previous studies.

Findings

28 candidate high-velocity stars identified

Sample includes the most promising 12 candidates

Demonstrates LAMOST's potential to discover diverse HVSs

Abstract

We report the discovery of 28 candidate high-velocity stars (HVSs) at heliocentric distances of less than 3 kpc, based on the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) Data Release 1. Our sample of HVS candidates covers a much broader color range than the equivalent ranges discussed in previous studies and comprises the first and largest sample of HVSs in the solar neighborhood. The sufficiently accurate observed and derived parameters for all candidates allow us to ascertain their nature as genuine HVSs, while a subset of 12 objects represents the most promising candidates. Our results also highlight the great potential of discovering statistically large numbers of HVSs of different spectral types in LAMOST survey data. This will ultimately enable us to achieve a better understanding of the nature of Galactic HVSs and their ejection mechanisms, and to constrain the structure of the Galaxy.