  A new large-area Washington M,T_2+DDO51 filter survey of more than 10 deg^2
around the Carina dSph galaxy reveals a spectroscopically confirmed power law
radial density "break" population of Carina giant stars extending several
degrees beyond the central King profile. Magellan telescope MIKE spectroscopy
establishes the existence of Carina stars to at least 4.5 times its central
King limiting radius, r_lim and primarily along Carina's major axis. To keep
these stars bound to the dSph would require a global Carina mass-to-light ratio
of M/L > 6,300 M/L_sun. The MIKE velocities, supplemented with ~950 additional
Carina field velocities from archived VLT+GIRAFFE spectra with r<=r_lim,
demonstrate a nearly constant Carina velocity dispersion to just beyond r =
r_lim, and both a rising velocity dispersion and a velocity shear at still
larger radii. Together, the observational evidence suggests that the discovered
extended Carina population represents tidal debris from the dSph. Of 65 giant
candidates at large angular radii from the Carina center for which MIKE spectra
have been obtained 94% are associated either with Carina or a second, newly
discovered diffuse, but strongly radial velocity-coherent (velocity dispersion
of 9.8 km s^-1), foreground halo system. The fifteen stars in this second,
retrograde velocity population have (1) a mean metallicity ~1 dex higher than
that of Carina, and (2) colors and magnitudes consistent with the red clump of
the Large Magellanic Cloud (LMC). Additional spectroscopy of giant star
candidates in fields linking Carina and the LMC shows a smooth velocity
gradient between the LMC and the retrograde Carina moving group. We conclude
that we have found Magellanic stars almost twice as far (22 deg) from the LMC
center than previously known.
