Spectroscopic and photometric surveys of the Milky Way and its stellar clusters in the Gaia era

TL;DR

This paper reviews the role of spectroscopic surveys in complementing Gaia data for studying the Milky Way and its clusters, highlighting current and future instrumentation and their scientific impact.

Contribution

It provides an overview of the scientific motivations, instrumentation requirements, and upcoming spectroscopic surveys that enhance Gaia's astrometric data for stellar cluster research.

Findings

Spectroscopic surveys are crucial for obtaining radial velocities and elemental abundances.

Current and future multi-object spectrographs will significantly advance cluster studies.

Rapid developments in instrumentation are expanding the scope of galactic surveys.

Abstract

This contribution to the Stellar Clusters & Associations: A RIA Workshop on Gaia deals with surveys of stars, in particular spectroscopic surveys, with attention to their impact on cluster studies, and their connectionwith Gaia. I review some of the scientific reasons why we want large spectroscopic surveys, what requirements these put on the instrumentation. Then I turn to a review of the current and future instrumentation that will enable us to complement Gaia's excellent distances and proper motions with the desired ground-based spectroscopy to obtain additional radial velocities and elemental abundances of high quality. This is a very fast moving area with several new surveys using existing and future multi-object spectrographs on 4- and 8-meter telescopes. As things change rapidly it is difficult to give adequate information on all these projects, but with the inclusion of links to the relevant web-sites the reader should be able to follow the latest developments as they unfold.