LAMOST Medium-Resolution Spectroscopic Survey (LAMOST-MRS): Scientific goals and survey plan

TL;DR

The LAMOST-MRS survey aims to collect high-quality medium-resolution spectra of about 2 million stars over five years, enabling detailed studies of stellar physics, binary systems, and variable stars.

Contribution

This paper outlines the scientific goals and survey plan for the first large-scale medium-resolution spectroscopic survey using LAMOST, including its scope, strategy, and expected scientific impact.

Findings

Expected to observe ~2 million stellar spectra.

Will provide ~200,000 stars with 60-epoch observations.

Spectra will include elemental abundances, velocities, and emission profiles.

Abstract

Since September 2018, LAMOST starts a new 5-year medium-resolution spectroscopic survey (MRS) using bright/gray nights. We present the scientific goals of LAMOST-MRS and propose a near optimistic strategy of the survey. A complete footprint is also provided. Not only the regular medium-resolution survey, but also a time-domain spectroscopic survey is being conducted since 2018 and will be end in 2023. According to the detailed survey plan, we expect that LAMOST-MRS can observe about 2 million stellar spectra with ~7500 and limiting magnitude of around G=15 mag. Moreover, it will also provide about 200 thousand stars with averagely 60-epoch observations and limiting magnitude of G~14 mag. These high quality spectra will give around 20 elemental abundances, rotational velocities, emission line profiles as well as precise radial velocity with uncertainty less than 1 km/s. With these data, we expect that LAMOST can effectively leverage sciences on stellar physics, e.g. exotic binary stars, detailed observation of many types of variable stars etc., planet host stars, emission nebulae, open clusters, young pre-main-sequence stars etc.