Related papers: Tombaugh 2: The First Open Cluster with a Signific…
Context. Open clusters are very good tracers of the evolution of the Galactic disc. Thanks to Gaia, their kinematics can be investigated with an unprecedented precision and accuracy. Aims. The distribution of open clusters in the 6D phase…
Since Gaia DR2 was released, many velocity structures in the disk have been revealed such as large scale ridge-like patterns in the phase space. Both kinematic information and stellar elemental abundances are needed to reveal their…
Spreads in light element abundances among stars (a.k.a. multiple populations) are observed in nearly all globular clusters. One way to map such chemical variations using high-precision photometry is to employ a suitable combination of…
To determine the nature of the recently discovered, ring-like stellar structure at the Galactic anticenter, we have collected spectra of a set of presumed constituent M giants selected from the 2MASS point source catalog. Radial velocities…
The globular cluster $\omega$ Centauri (NGC 5139) is a puzzling stellar system harboring several distinct stellar populations whose origin still represents a unique astrophysical challenge. Current scenarios range from primordial chemical…
High-resolution optical spectra of eighteen blue horizontal-branch (BHB) stars in the globular cluster M15 indicate that their stellar rotation rates and photospheric compositions vary strongly as a function of effective temperature. Among…
We present internal velocity dispersions and precise radial velocities for 200 globular clusters (GCs) in M31 that are derived using new high-resolution spectra from MMT/Hectochelle. Of these, 163 also have King model structural parameters…
Context. Globular clusters are known to host multiple stellar populations, which are a signature of their formation process. The globular cluster E3 is one of the few low-mass globulars that is thought not to host multiple populations.…
We summarize radial velocity studies of selected stars in the old, distant clusters Berkeley 20, Berkeley 21, NGC 2141, Berkeley 29, and Berkeley 31. Three members of M67 were observed similarly, and those velocities compare extremely well…
Because of the continuous variations in mass, metallicity, and opacity, dwarf stars are distributed along the main sequence on optical and near-IR color-magnitude diagrams following a smooth polynomial. In this study of utilizing a catalog…
Recent work on metal-intermediate globular clusters (GCs) with [Fe/H]=$-1.5$ and $-0.75$ has illustrated the theoretical behavior of multiple populations in photometric diagrams obtained with the James Webb Space Telescope (JWST). These…
At the "New Horizons in Globular Cluster Astronomy" conference (Padova, June 2002), two members of the VLT globular cluster team presented different views on the importance of heavy-element sedimentation in Population II stars: "The lack of…
Despite their shared origin, members of globular clusters display star-to-star variations in composition. The observed pattern of element abundances is unique to these stellar environments, and cannot be fully explained by any proposed…
Abundance trends in heavier elements with evolutionary phase have been shown to exist in the globular cluster NGC 6752 [Fe/H]=-1.6. These trends are a result of atomic diffusion and additional (non-convective) mixing. Studying such trends…
Atomic diffusion in stars can create systematic trends of surface abundances with evolutionary stage. Globular clusters offer useful laboratories to put observational constraints on this theory as one needs to compare abundances in…
Recently, combining radial velocities from Keck/HIRES echelle spectra with published proper motion membership probabilities, Cote et al (2002) observed a sample of 21 stars, probable members of Palomar 13, a globular cluster in the Galactic…
The young open cluster Dolidze 25, in the direction of the Galactic Anticentre, has been attributed a very low metallicity, with typical abundances between $-0.5$ and $-0.7$ dex below solar. We intend to derive accurate cluster parameters…
We identify a new, nearby (0.5 < d < 10 kpc) stream in data from the RAdial Velocity Experiment (RAVE). As the majority of stars in the stream lie in the constellation of Aquarius we name it the Aquarius Stream. We identify 15 members of…
With the exception of Terzan 5, all the Galactic globular clusters that possess significant metallicity spreads, such as omega Cen and M22, are preferentially the more luminous clusters with extended horizontal branches. Here we present…
We analyze radial velocities for a sample of 31 Class I and flat spectrum protostars in Taurus-Auriga, rho Ophiuchi and Serpens for evidence of the global dynamical state of extremely young stellar populations buried within parental…