High-velocity streams in the Milky Way halo with the SDSS and GSC-II kinematic survey
1 INAF - Astronomical Observatory of Torino, Italy
2 National Optical Astronomy Observatory, Tucson, AZ, USA
3 Michigan State University and JINA, E. Lansing, MI, USA
a e-mail: email@example.com
We explore the stellar halo of the Milky Way to search for fossil signatures of past mergers, consisting of streams of particles torn from their progenitors during the process of hierarchical merging. We examine a representative sample of about 2 700 halo subdwarfs in the solar neighborhood, selected from a new kinematic survey produced by means of spectrophotometric data from the Sloan Digital Sky Survey, and high-quality proper motions derived from multi-epoch positions using the Guide Star Catalog II. We find statistical evidence for discrete overdensities, likely possible accretion remnants. This methodology and the quality of the selected sample are an efficient means to discover new members of known streams and to identify new streams themselves, and set the basis for future studies.
© Owned by the authors, published by EDP Sciences, 2012