We have measured radial velocities and metallicities of sixteen RR Lyrae stars from the QUEST survey in the Sagittarius tidal stream at 50 kpc from the Galactic Center. The distribution of velocities is quite narrow (sigma = 25 km s(-1)) indicating that the structure is coherent also in velocity space. The mean heliocentric velocity in this part of the stream is 32 km s-1. The mean metallicity of the RR Lyrae stars is [Fe/H] = -1.7. Both results are consistent with previous studies of red giant stars in this part of the stream. The velocities also agree with a theoretical model of the disruption of the Sagittarius galaxy.
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