Mapping the galactic halo. V. Sagittarius dwarf spheroidal tidal debris 60degrees from the main body

As part of the Spaghetti Project Survey, we have detected a concentration o f giant stars well above expectations for a smooth halo model. The position (l similar to 350 degrees, b similar to 50 degrees) and distance (similar to 50 kpc) of this concentration match those of the northern overdensity de tected by the Sloan Digital Sky Survey. We find additional evidence for str ucture at similar to 80 kpc in the same direction. We present radial veloci ties for many of these stars, including the first published results from th e 6.5 m Magellan telescope. The radial velocities for stars in these struct ures are in excellent agreement with models of the dynamical evolution of t he Sagittarius dwarf tidal debris, whose center is 60 degrees away. The met allicity of stars in these streams is lower than that of the main body of t he Sgr dwarf, which may indicate a radial metallicity gradient prior to dis ruption.