Selecting Sagittarius: Identification and Chemical Characterization of the Sagittarius Stream
Year: 2015
Type: article
Abstract: Wrapping around the Milky Way, the Sagittarius stream is the dominant substructure in the halo. Our statistical selection method has allowed us to identify 106 highly likely members of the Sagittarius stream. Spectroscopic analysis of metallicity and kinematics of all members provides us with a new mapping of the Sagittarius stream. We find correspondence between the velocity distribution of stream stars and those computed for a triaxial model of the Milky Way dark matter halo. The Sagittarius trailing arm exhibits a metallicity gradient, ranging from −0.59 to −0.97 dex over 142°. This is consistent with the scenario of tidal disruption from a progenitor dwarf galaxy that possessed an internal metallicity gradient. We note high metallicity dispersion in the leading arm, causing a lack of detectable gradient and possibly indicating orbital phase mixing. We additionally report on a potential detection of the Sextans dwarf spheroidal in our data.
Source: The Astrophysical Journal
Authors: E. A. Hyde, S. Keller, D. B. Zucker, R. Ibata, A. Siebert, G. F. Lewis, J. Penarrubia, M. Irwin, G. Gilmore, R. R. Lane, A. Koch, A. R. Conn, F. I. Diakogiannis, S. Martell
Institutions: Western Sydney University, Macquarie University, Australian National University, Australian Astronomical Observatory, Centre National de la Recherche Scientifique, Observatoire astronomique de Strasbourg, Université de Strasbourg, The University of Sydney, Royal Observatory, University of Edinburgh, University of Cambridge, University of Concepción, Heidelberg University, The University of Western Australia, International Centre for Radio Astronomy Research, UNSW Sydney
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
Awards: G1953547991, Cambridge Astronomical Survey Unit Project Portfolio, The Gaia-ESO Milky Way Survey, Astronomy Observation and Theory Consolidated Grant 2012, Cambridge Astronomical Survey Unit (CASU) - 2015 - 2016, Astronomy and Astrophysics at Edinburgh, The GALAH survey: A million-star exploration of Galactic history
OpenAlex ID: W1707320431