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We present results from a medium-resolution (R∼2000) spectroscopic follow-up campaign of 1694 bright (V<13.5), very metal-poor star candidates from the RAdial Velocity Experiment (RAVE). Initial selection of the low-metallicity targets was based on the stellar parameters published in RAVE Data Releases 4 and 5. Follow up was accomplished with the Gemini-N and Gemini-S, the ESO/NTT, the KPNO/Mayall, and the SOAR telescopes. The wavelength coverage for most of the observed spectra allows for the determination of carbon and α-element abundances, which are crucial for considering the nature and frequency of the carbon-enhanced metalpoor (CEMP) stars in this sample. We find that 88% of the observed stars have Fe H [ ]−1.0, 61% have Fe H [ ]−2.0, and 3% have Fe H [ ]−3.0 (with four stars at Fe H [ ]−3.5). There are 306 CEMP star candidates in this sample, and we identify 169 CEMP GroupI, 131 CEMP GroupII, and 6 CEMP GroupIII stars from the A(C) versus [Fe/H] diagram. Inspection of the C a [ ] abundance ratios reveals that five of the CEMP GroupII stars can be classified as "mono-enriched second-generation" stars. Gaia DR1 matches were found for 734 stars, and we show that transverse velocities can be used as a confirmatory selection criteria for low-metallicity candidates. Selected stars from our validated list are being followed-up with high-resolution spectroscopy to reveal their full chemical-abundance patterns for further studies.

We compare the distribution in position and velocity of nearby stars from the GaiaDR2 radial velocity sample with predictions of current theories for spirals in disc galaxies. Although the rich substructure in velocity space contains the same information, we find it more revealing to reproject the data into action-angle variables, and we describe why resonant scattering would be more readily identifiable in these variables. We compute the predicted changes to the phase space density, in multiple different projections, that would be caused by a simplified isolated spiral pattern, finding widely differing predictions from each theory. We conclude that the phase space structure present in the Gaia data shares many of the qualitative features expected in the transient spiral mode model. We argue that the popular picture of apparently swing-amplified spirals results from the superposition of a few underlying spiral modes.

We present results from an observing campaign to identify low-metallicity stars in the Best & Brightest Survey. From medium-resolution (R ∼ 1, 200 − 2, 000) spectroscopy of 857 candidates, we estimate the stellar atmospheric parameters (T eff , log g, and [Fe/H]), as well as carbon and α-element abundances. We find that 69% of the observed stars have [Fe/H] ≤ −1.0, 39% have [Fe/H] ≤ −2.0, and 2% have [Fe/H] ≤ −3.0. There are also 133 carbon-enhanced metal-poor (CEMP) stars in this sample, with 97 CEMP Group I and 36 CEMP Group II stars identified in the A(C) versus [Fe/H] diagram. A subset of the confirmed low-metallicity stars were followed-up with high-resolution spectroscopy, as part of the R-process Alliance, with the goal of identifying new highly and moderately r-processenhanced stars. Comparison between the stellar atmospheric parameters estimated in this work and from high-resolution spectroscopy exhibit good agreement, confirming our expectation that mediumresolution observing campaigns are an effective way of selecting interesting stars for further, more targeted, efforts.