Abundances and Kinematics of Field Stars. II. Kinematics and Abundance Relationships

As an investigation of the origin of ``$\alpha$-poor'' halo stars, we analyzekinematic and abundance data for 73 intermediate metallicity stars ($-1 >$[Fe/H] $\geq -2$) selected from Paper I of this series. We find evidence for aconnection between the kinematics and the enhancement of certainelement-to-iron ([X/Fe]) ratios in these stars. Statistically significantcorrelations were found between [X/Fe] and galactic rest-frame velocities(\vrf{}) for Na, Mg, Al, Si, Ca and Ni, with marginally significantcorrelations existing for Ti and Y as well. We also find that the [X/Fe] ratiosfor these elements all correlate with a similar level of significance with[Na/Fe]. Finally, we compare the abundances of these halo stars against thoseof stars in nearby dSph galaxies. We find significant differences between theabundance ratios in the dSph stars and halo stars of similar metallicity. Fromthis result, it is unlikely that the halo stars in the solar neighborhood,including even the ``$\alpha$-poor'' stars, were once members of disrupted dSphgalaxies similar to those studied to date.Comment: Accepted for publication in January 2002 AJ. 29 pages, 12 figures, 2 table