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The AB Dor Moving Group consists of a "nucleus" of ~10 stars at d ~ 20 pc,along with dozens of purported "stream" members distributed across the sky. Weperform a chemical and kinematic analysis of a subsample of AB Dor stream starsto test whether they constitute a physical stellar group. We use the NEMOGalactic kinematic code to investigate the orbits of the stream members, andperform a chemical abundance analysis using high resolution spectra taken withthe Magellan Clay 6.5-m telescope. Using a chi^2 test with the measuredabundances for 10 different elements, we find that only half of the purportedAB Dor stream members could possibly constitute a statistically chemicallyhomogeneous sample. Some stream members with 3D velocities were hundreds ofparsecs from the AB Dor nucleus ~10^8 yr ago, and hence were unlikely to sharea common origin. We conclude that the published lists of AB Dor moving groupstream members are unlikely to represent the dispersed remnant of a single starformation episode. A subsample of the stream stars appears to be bothstatistically chemically homogeneous and in the vicinity of the AB Dor nucleusat birth. Their mean metallicity is [Fe/H] = 0.02 +/- 0.02 dex, which weconsider representative for the AB Dor group. Finally, we report a strong lowerlimit on the age of the AB Dor nucleus of >110 Myr based on the pre-MScontraction times for K-type members which have reached the main sequence.

A Kine-Chemical Investigation of the AB Dor Moving Group "Stream"