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Radial velocities of 2768 fundamental mode RR Lyrae stars (RRLs) toward theSouthern Galactic bulge are presented, spanning the southern bulge from -8 < l< +8 and -3 < b <-6. Distances derived from the pulsation properties of theRRLs are combined with Gaia proper motions to give constraints on the orbitalmotions of 1389 RRLs. The majority (~75%) of the bulge RRLs have orbitsconsistent with these stars being permanently bound to <3.5 kpc from theGalactic Center, similar to the bar. However, unlike the bulge giants, the RRLsexhibit slower rotation and a higher velocity dispersion. The higher velocitydispersion arises almost exclusively from halo interlopers passing through theinner Galaxy. We present 82 stars with space velocities > 500 km/s and findthat the majority of these high-velocity stars are halo interlopers; it isunclear if a sub-sample of these stars with similar space velocities have acommon origin. Once the 25% of the sample represented by halo interlopers iscleaned, we can clearly discern two populations of bulge RRLs in the innerGalaxy. One population of RRLs is not as tightly bound to the Galaxy (but isstill confined to the inner ~3.5 kpc), and is both spatially and kinematicallyconsistent with the barred bulge. The second population is more centrallyconcentrated and does not trace the bar. One possible interpretation is thatthis population was born prior to bar formation, as its spatial location,kinematics and pulsation properties suggest, possibly from an accretion eventat high redshift.

The Bulge Radial Velocity Assay for RR Lyrae stars (BRAVA-RR) DR2: a Bimodal Bulge?