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We have used the AAOMEGA spectrograph to obtain R $\sim 1500$ spectra of 714stars that are members of two red clumps in the Plaut Window Galactic bulgefield $(l,b)=0^{\circ},-8^{\circ}$. We discern no difference between the clumppopulations based on radial velocities or abundances measured from the Mg$b$index. The velocity dispersion has a strong trend with Mg$b$-index metallicity,in the sense of a declining velocity dispersion at higher metallicity. We alsofind a strong trend in mean radial velocity with abundance. Our red clumpsample shows distinctly different kinematics for stars with [Fe/H] $<-1$, whichmay plausibly be attributable to a minority classical bulge or inner halopopulation. The transition between the two groups is smooth. Thechemo-dynamical properties of our sample are reminiscent of those of the MilkyWay globular cluster system. If correct, this argues for no bulge/halodichotomy and a relatively rapid star formation history. Large surveys of thecomposition and kinematics of the bulge clump and red giant branch are neededto define further these trends.

Separating the conjoined red clump in the Galactic Bulge: Kinematics and Abundances