[Previous] | [Session 112] | [Next]

[112.12] Tidal streams from dwarf spheroidal galaxies as diagnostics of the structure of the Milky Way halo

M. Eftimova (DePaul University), M. Valluri (University of Chicago)

Since the discovery of the Sagittarius dwarf galaxy in 1994 many groups have sought to model the observed tidal streams in the Milky Way halo to infer the structure and distribution of the dark matter. Recent measurements of radial velocities of the stars in several streams indicate that the streams have small stellar velocity dispersions (~ 20-30 km/s) which are comparable to the internal velocity dispersions of dwarf spheroids. Simulations of the evolution of tidal streams in clumpy triaxial dark matter halo with the properties predicted by CDM cosmogonies suggest that the tidal debris will undergo differential precession and small scale heating which will disperse them in a very short timescale. In this poster we present a semi-analytic study of the phase-space structure of a model Milky Way potential with different degrees of substructure to determine how effectively the kinematical properties - particularly the small stellar velocity dispersions - of the observed tidal streams can place constraints on the properties of the substructure in the Milky Way halo.

The author(s) of this abstract have provided an email address for comments about the abstract: magdalenateftimova@hotmail.com

[Previous] | [Session 112] | [Next]

Bulletin of the American Astronomical Society, 35#5
© 2003. The American Astronomical Soceity.