Bibcode
Majewski, Steven R.; Allende-Prieto, C.; Beers, T. C.; Bizyaev, D. M.; Frinchaboy, P. M.; Garcia-Perez, A.; Holtzman, J.; Ivans, I. I.; Law, D. R.; Nidever, D. L.; Schiavon, R. P.; Shetrone, M.; Skrutskie, M. F.; Wilson, J. C.; Zasowski, G.
Referencia bibliográfica
American Astronomical Society, AAS Meeting #219, #410.05
Fecha de publicación:
1
2012
Número de citas
2
Número de citas referidas
2
Descripción
The Apache Point Observatory Galactic Evolution Experiment (APOGEE),
part of the Sloan Digital Sky Survey III, is exploring the stellar
populations of the Milky Way using the Sloan 2.5-m telescope linked to a
high resolution (R 22,500), near-infrared (1.51-1.68 microns)
spectrograph with 300 optical fibers. For about 100,000, predominantly
red giant branch stars that APOGEE is targeting across the Galactic
bulge, disks and halo, the collected high S/N (>100 per
Nyquist-limit-sized pixel) spectra will provide accurate (+/-200 m/s)
radial velocities, stellar atmospheric parameters, and precise (+/- 0.1
dex) chemical abundances for about 15 chemical species. The APOGEE
survey targeting plan includes fields that have been specifically placed
on either the core or tails of the Sagittarius (Sgr) dSph galaxy. Some
of the target selection has relied on known or suspected giant star
members of Sgr identified in previous surveys. But other fields in the
path of the Sgr stream serendipitously uncover additional Sgr stars
through the normal APOGEE giant star targeting. We report on early
results from APOGEE commissioning data that include dozens of Sgr stars
spread over several distinct pointings on the Sgr core. In addition, we
report the discovery of Sgr stars found in several pointings directed at
the Galactic bulge and midplane. These data for Sgr stars lying behind
some of the dustiest parts of the Milky Way yield accurate velocities,
velocity dispersions and chemical information on stretches of the
Sagittarius stream never before explored. The results can be used to
refine models of the chemodynamical evolution of the Sgr system and the
shape of the gravitational potential of the Milky Way.