SEGUE: A Spectroscopic Survey of 240,000 stars with g=14-20

TL;DR

SEGUE conducted a large-scale spectroscopic survey of 240,000 faint Milky Way stars, providing valuable data on stellar properties and Galactic structure, with publicly accessible spectra, imaging, and parameters.

Contribution

This paper introduces the SEGUE survey, which uniquely combines extensive spectroscopic and imaging data for a large sample of Milky Way stars, enabling detailed Galactic studies.

Findings

Spectra obtained for 240,000 stars across three-quarters of the sky.

Radial velocity accuracy of 4 km/s for bright stars, 15 km/s at g=20.

Derived stellar parameters for stars with high S/N.

Abstract

The SEGUE survey obtained 240,000 moderate resolution (R = 1800) spectra from 3900 - 9000 Angstroms of fainter Milky Way stars (14.0 < g < 20.3) of a wide variety of spectral types, both main sequence and evolved objects, with the goal of studying the kinematics and populations of our Galaxy and its halo. The spectra are clustered in 212 regions spaced over three-quarters of the sky. Radial velocity accuracies for stars are 4 km/s at g < 18, degrading to 15 km/s at g = 20. For stars with S/N > 10 per resolution element, stellar atmospheric parameters are estimated, including metallicity, surface gravity, and effective temperature. SEGUE obtained 3500 square degrees of additional ugriz imaging (primarily at low Galactic latitudes) providing precise multi-color photometry (g,r,i = 2%), (u,z = 3%) and astrometry (0.1 arcsec) for spectroscopic target selection. The stellar spectra, imaging data, and derived parameter catalogs for this survey are publicly available as part of SDSS Data Release 7 (DR7).