EPJ Web of Conferences
Volume 19, 2012Assembling the Puzzle of the Milky Way
|Number of page(s)||5|
|Section||First Epochs Assembly: Halo Assembly, Streams, Which Timescale?|
|Published online||07 February 2012|
Mapping the Galactic halo with main-sequence and RR Lyrae stars
Division of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, CA 91125, USA
a e-mail: firstname.lastname@example.org
We present an analysis of Galactic halo structure, substructure, and metallicity traced by main-sequence and RR Lyrae stars selected from the SDSS stripe 82 and CFHT Legacy Survey data sets. The main result of the study based on SDSS stripe 82 data is a 2D map of the Galactic halo that reaches distances of 100 kpc and traces previously known and new halo substructures, such as the Sagittarius and Pisces tidal streams. We present strong direct evidence, based on both RR Lyrae and main-sequence stars, that the halo stellar number density profile significantly steepens beyond 30 kpc from the Galactic center. The steepening of the density profile beyond 30 kpc is also evident in the distribution of main-sequence stars observed by the CFHT Legacy Survey along four Galactic lines of sight. In the two CFHT sightlines where we do not detect significant substructure, the median metallicity is found to be independent of distance within systematic uncertainties ([Fe∕H] ~ −1.5 ± 0.1 dex within 30 kpc of the Galactic Center).
© Owned by the authors, published by EDP Sciences, 2012
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.