- ID:
- ivo://CDS.VizieR/J/MNRAS/419/2844
- Title:
- Radial metallicity gradient from RAVE DR3
- Short Name:
- J/MNRAS/419/2844
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate radial metallicity gradients for a sample of dwarf stars from the RAdial Velocity Experiment (RAVE) Data Release 3 (DR3, Cat. III/265). We select a total of approximately 17000 F-type and G-type dwarfs, using a selection of colour, log g and uncertainty in the derived space motion, and calculate for each star a probabilistic (kinematic) population assignment to a thick or thin disc using space motion and additionally another (dynamical) assignment using stellar vertical orbital eccentricity. We additionally subsample by colour, to provide samples biased toward young thin-disc and older thin-disc stars. We derive a metallicity gradient as a function of Galactocentric radial distance, i.e. d[M/H]/dRm=-0.051+/-0.005dex/kpc, for the youngest sample, F-type stars with vertical orbital eccentricities e_v_<=0.04. Samples biased toward older thin-disc stars show systematically shallower abundance gradients.
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Search Results
- ID:
- ivo://CDS.VizieR/III/172
- Title:
- Radial Velocities from Objective Prism Plates
- Short Name:
- III/172
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Accurate positions and radial velocities are determined from 32 objective-prism plates for two areas. Each field is observed twice with opposite dispersion, allowing adjustment of coordinates for spectra not at the plate centers. From the adjusted coordinates and plate overlap, positions are determined with average mean errors: 0.0135 s in RA and 0.177 arcsec in Dec for Area I (near the South Galactic Pole); 0.0315 s in RA, 0.144 arcsec in Dec for Area II (near the galactic plane). Observations were taken by J.D. MacConnell and G. Araya with a six degree prism on the Curtis Schmidt telescope at Cerro Tololo.
- ID:
- ivo://CDS.VizieR/J/A+A/473/143
- Title:
- Radial velocities of C stars near Galactic plane
- Short Name:
- J/A+A/473/143
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The availability, from 2MASS, of a large homogeneous sample of Galactic C stars and the recognition that their absolute magnitude can be accurately determined offer the possibility to use them as kinematical probes to investigate motions in the thin or thick disks. Our aims is to determine the radial velocities for 70 C stars, a few degrees from the Galactic plane and distributed in longitudes from 60{deg} to 220{deg}.
- ID:
- ivo://CDS.VizieR/J/AJ/149/53
- Title:
- Radial velocities of 12 Milky Way globular clusters
- Short Name:
- J/AJ/149/53
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present central velocity dispersions, masses, mass-to-light ratios (M/Ls), and rotation strengths for 25 Galactic globular clusters (GCs). We derive radial velocities of 1951 stars in 12 GCs from single order spectra taken with Hectochelle on the MMT telescope. To this sample we add an analysis of available archival data of individual stars. For the full set of data we fit King models to derive consistent dynamical parameters for the clusters. We find good agreement between single-mass King models and the observed radial dispersion profiles. The large, uniform sample of dynamical masses we derive enables us to examine trends of M/L with cluster mass and metallicity. The overall values of M/L and the trends with mass and metallicity are consistent with existing measurements from a large sample of M31 clusters. This includes a clear trend of increasing M/L with cluster mass and lower than expected M/Ls for the metal-rich clusters. We find no clear trend of increasing rotation with increasing cluster metallicity suggested in previous work.
- ID:
- ivo://CDS.VizieR/J/ApJ/813/89
- Title:
- Radial velocities of Milky Way inner halo stars
- Short Name:
- J/ApJ/813/89
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We measure the three components of velocity dispersion, {sigma}_R_, {sigma}_{theta}_, {sigma}_{phi}_, for stars within 6<R<30kpc of the Milky Way using a new radial velocity sample from the MMT telescope. We combine our measurements with previously published data so that we can more finely sample the stellar halo. We use a maximum likelihood statistical method for estimating mean velocities, dispersions, and covariances assuming only that velocities are normally distributed. The alignment of the velocity ellipsoid is consistent with a spherically symmetric gravitational potential. From the spherical Jeans equation, the mass of the Milky Way is M(R<=12kpc)=1.3x10^11^M_{sun}_ with an uncertainty of 40%. We also find a region of discontinuity, 15<~R<~25kpc, where the estimated velocity dispersions and anisotropies diverge from their anticipated values, confirming the break observed by others. We argue that this break in anisotropy is physically explained by coherent stellar velocity structure in the halo, such as the Sgr stream. To significantly improve our understanding of halo kinematics will require combining radial velocities with future Gaia proper motions.
- ID:
- ivo://CDS.VizieR/J/AJ/101/625
- Title:
- Radial velocities of NGP wide binaries
- Short Name:
- J/AJ/101/625
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present precise radial velocities from a survey of 247 stars centered on Selected Area 57 at the North Galactic Pole, complete for late-type stars with V magnitude brighter than 12.0. The radial velocities have a typical precision of 0.2-0.3km/s. New spectral types and distances estimates are presented for 120 of the stars in the sample. We have considered all pairs of stars with angular separations between 1 and 600arcsec, and find 11 candidate pairs with velocity differences less than 1.5km/s. We estimate that 4 or 5 of the 11 candidate pairs are actually bound binaries, but none with separations larger than 0.1pc. The constraints imposed by these results on the actual distribution of wide binaries in the Galaxy should now be reanalyzed. The unusual precision of our velocities led to the discovery of a new cluster associated with the multiple system ADS 8811 ABC.
- ID:
- ivo://CDS.VizieR/J/ApJS/237/27
- Title:
- Radio Ammonia Mid-plane Survey (RAMPS) pilot survey
- Short Name:
- J/ApJS/237/27
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Radio Ammonia Mid-Plane Survey (RAMPS) is a molecular line survey that aims to map a portion of the Galactic midplane in the first quadrant of the Galaxy (l=10{deg}-40{deg}, |b|<=0.4{deg}) using the Green Bank Telescope. We present results from the pilot survey, which has mapped approximately 6.5 square degrees in fields centered at l=10{deg}, 23{deg}, 24{deg}, 28{deg}, 29{deg}, 30{deg}, 31{deg}, 38{deg}, 45{deg}, and 47{deg}. RAMPS observes the NH3 inversion transitions NH_3_(1,1)-(5,5), the H_2_O 6_1,6_-5_2,3_ maser line at 22.235GHz, and several other molecular lines. We present a representative portion of the data from the pilot survey, including NH_3_(1,1) and NH_3_(2,2) integrated intensity maps, H_2_O maser positions, maps of NH_3_ velocity, NH_3_ line width, total NH_3_ column density, and NH_3_ rotational temperature.
- ID:
- ivo://CDS.VizieR/J/A+A/511/A90
- Title:
- RAVE DR2 distance catalogue
- Short Name:
- J/A+A/511/A90
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We develop a method for deriving distances from spectroscopic data and obtaining full 6D phase-space coordinates for the RAVE survey's second data release.
- ID:
- ivo://CDS.VizieR/J/A+A/600/A106
- Title:
- RAVE open cluster pairs, groups and complexes
- Short Name:
- J/A+A/600/A106
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Galactic open clusters (OCs) mainly belong to the young stellar population in the Milky Way disk, but are there groups and complexes of OCs that possibly define an additional level in hierarchical star formation? Current compilations are too incomplete to address this question, especially regarding radial velocities (RVs) and metallicities ([M/H]). Here we present the parameters for the final working sample of 432 open clusters, as well as the mean parameters for the 19 detected potential open cluster groupings.
- ID:
- ivo://CDS.VizieR/III/265
- Title:
- RAVE 3rd data release
- Short Name:
- III/265
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the third data release of the RAdial Velocity Experiment (RAVE) which is the first milestone of the RAVE project, releasing the full pilot survey. The catalog contains 83,072 radial velocity measurements for 77,461 stars in the southern celestial hemisphere, as well as stellar parameters for 39,833 stars. This paper describes the content of the new release, the new processing pipeline, as well as an updated calibration for the metallicity based upon the observation of additional standard stars. Spectra will be made available in a future release. The data release can be accessed via the RAVE Web site http://www.rave-survey.org.
