APOGEE: Probing the Evolution of the Milky Way

APO Galactic Evolution Experiment 1 (APOGEE-1)

APOGEE-1 at a Glance:

  • Bright time observations
  • Spring 2011 – Spring 2014
  • 150,000 giant and dwarf stars in the Galactic bulge, disk, and halo
  • Resolution R~22,500, typical S/N > 100
  • Wavelengths 1.51-1.70 μm
  • Stellar parameters including log(g), Teff, [Fe/H], [α/Fe]
  • Abundance of 15 chemical species to 0.1 dex precision
  • Velocity uncertainties < 100 m/s

For a detailed description of APOGEE-1, see section 5 of the Project Description, available as a PDF document.

The APO Galactic Evolution Experiment 1 (APOGEE-1) employed high-resolution, high signal-to-noise infrared spectroscopy to penetrate the dust that obscures significant fractions of the disk and bulge of our Galaxy. APOGEE surveyed over 100,000 red giant stars across the full range of the Galactic bulge, bar, disk, and halo. APOGEE-1 generated precise radial velocities and detailed chemical abundances, providing unprecedented insights into the dynamical structure and chemical history of the Galaxy. In conjunction with the planet-finding surveys, Kepler and CoRoT, APOGEE unravels problems in fundamental astrophysics.

The SEGUE-2 and APOGEE-1 datasets will play a central role in near-field cosmology tests of galaxy formation and the small-scale distribution of dark matter.

IR image of the inner Galaxy, showing the plane and bulge of the Galaxy full of stars and dust. APOGEE-1 used new IR instrumentation, which is less affected by the extinction from interstellar dust, to study stars within the disk (now continued in <a href="http://www.sdss.org/surveys/apogee-2/">APOGEE-2</a>). <i>Image: 2MASS</i>
IR image of the inner Galaxy, showing the plane and bulge of the Galaxy full of stars and dust. APOGEE-1 used new IR instrumentation, which is less affected by the extinction from interstellar dust, to study stars within the disk (now continued in APOGEE-2). Image: 2MASS

Working with APOGEE-1 data

Data Release 14 is the latest public release of APOGEE-1 spectra, which includes newly reduced spectra and new and improved abundances.

  • An overview of the APOGEE data available (including APOGEE-1 and APOGEE-2) is given here.
  • There are some examples of accessing and viewing APOGEE-1 data available here.
  • The target selection for APOGEE-1 stars is described here (originally from DR13). See APOGEE-2 details here.

APOGEE-1 papers

The APOGEE-1 team has submitted and/or published several papers which are listed on the SDSS-III APOGEE Publications page.