Galactic Archeology - requirements on survey spectrographs

TL;DR

Galactic Archeology uses stellar data to understand the Milky Way's formation, requiring specific spectrograph instrumentation and calibration to complement Gaia's data, with focus on radial velocities and elemental abundances.

Contribution

This paper reviews the instrumentation requirements and calibration needs for ground-based spectrographs to support Galactic Archeology in conjunction with Gaia.

Findings

Gaia revolutionizes Galactic Archeology studies.

Ground-based spectroscopy is essential for faint stars.

Instrumental and calibration challenges impact abundance analysis.

Abstract

Galactic Archeology is about exploring the Milky Way as a galaxy by, mainly, using its (old) stars as tracers of past events and thus figure out the formation and evolution of our Galaxy. I will briefly outline some of the key scientific aspects of Galactic Archeology and then discuss the associated instrumentations. Gaia will forever change the way we approach this subject. However, Gaia on its own is not enough. Ground-based complementary spectroscopy is necessary to obtain full phase-space information and elemental abundances for stars fainter than the top few percent of the bright part of the Gaia catalogue. I will review the requirement on instrumentation for Gaia follow-up that Galactic Archeology sets. In particular, I will discuss the requirements on radial velocity and elemental abundance determination, including a brief look at potential pit-falls in the abundance analysis (e.g., NLTE, atomic diffusion). This contribution also provides a non-exhaustive comparison of the various current and future spectrographs for Galactic Archeology. Finally, I will discuss the needs for astrophysical calibrations for the surveys and inter-survey calibrations.