- ID:
- ivo://CDS.VizieR/J/A+A/537/A83
- Title:
- Abunbances of 9 red giants of Pal 14
- Short Name:
- J/A+A/537/A83
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Chemical abundances of 25 elements, which include {alpha}-, iron peak-, and neutron-capture elements, in the outer halo globular cluster Palomar 14 have been determined for the nine red giants observed with the FLAMES/UVES spectrograph. The abundance pattern of Pal 14 is similar to the inner halo GCs, halo field stars, and GCs of recognized extragalactic origin, but differs from what is customarily found in dSphs field stars. The abundance properties of Pal 14 as well as those of the other outer halo GCs are thus compatible with an accretion origin from dSphs. The neutron-capture elements show an r-process signature.
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- ID:
- ivo://CDS.VizieR/J/A+A/619/A178
- Title:
- Abundance analysis of 4 red giants in NGC 6558
- Short Name:
- J/A+A/619/A178
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- NGC 6558 is a bulge globular cluster with a blue horizontal branch (BHB), combined with a metallicity of [Fe/H]~-1.0. It is similar to HP 1 and NGC 6522, which could be among the oldest objects in the Galaxy. Element abundances in these clusters could reveal the nature of the first supernovae. We aim to carry out detailed spectroscopic analysis for four red giants of NGC 6558, in order to derive the abundances of the light elements C, N, O, Na, Al, the {alpha}-elements Mg, Si, Ca, Ti, and the heavy elements Y, Ba, and Eu. High-resolution spectra of four stars with FLAMES-UVES@VLT UT2-Kueyen were analysed. Spectroscopic parameter-derivation was based on excitation and ionization equilibrium of FeI and FeII. This analysis results in a metallicity of [Fe/H]=-1.17+/-0.10 for NGC 6558. We find the expected {alpha}-element enhancements in O and Mg with [O/Fe]=+0.40, [Mg/Fe]=+0.33, and low enhancements in Si and Ca. Ti has a moderate enhancement of [Ti/Fe]=+0.22. The r-element Eu appears very enhanced with a mean value of [Eu/Fe]=+0.63. The first peak s-elements Y and Sr are also enhanced, these results have however to be treated with caution, given the uncertainties in the continuum definition; the use of neutral species (Sr I, YI), instead of the dominant ionized species is another source of uncertainty. Ba appears to have a solar abundance ratio relative to Fe. NGC 6558 shows an abundance pattern that could be typical of the oldest inner bulge globular clusters, together with the pattern in the similar clusters NGC 6522 and HP 1. They show low abundances of the odd-Z elements Na and Al, and of the explosive nucleosynthesis {alpha}-elements Si, Ca, and Ti. The hydrostatic burning {alpha}-elements O and Mg are normally enhanced as expected in old stars enriched with yields from core-collapse supernovae, and the iron-peak elements Mn, Cu, Zn show low abundances, which is expected forMn and Cu, but not for Zn. Finally, the cluster trio NGC 6558, NGC 6522 and HP 1 have relatively high abundances of first-peak heavy elements, variable second-peak element Ba, and the r-element Eu is enhanced. The latter is particularly high in NGC 6558.
- ID:
- ivo://CDS.VizieR/J/AJ/142/63
- Title:
- Abundance of five stars in NGC 6397
- Short Name:
- J/AJ/142/63
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present chemical abundances in three red giants and two turnoff (TO) stars in the metal-poor Galactic globular cluster (GC) NGC 6397 based on spectroscopy obtained with the Magellan Inamori Kyocera Echelle high-resolution spectrograph on the Magellan 6.5m Clay telescope. Our results are based on a line-by-line differential abundance analysis relative to the well-studied red giant Arcturus and the Galactic halo field star HIP 66815.
- ID:
- ivo://CDS.VizieR/J/ApJ/754/L38
- Title:
- Abundances and radial velocities of M13 giants
- Short Name:
- J/ApJ/754/L38
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present O, Na, and Fe abundances, as well as radial velocities, for 113 red giant branch (RGB) and asymptotic giant branch (AGB) stars in the globular cluster M13. The abundances and velocities are based on spectra obtained with the WIYN-Hydra spectrograph, and the observations range in luminosity from the horizontal branch (HB) to RGB tip. The results are examined in the context of recent globular cluster formation scenarios. We find that M13 exhibits many key characteristics that suggest its formation and chemical enrichment are well described by current models. Some of these observations include the central concentration of O-poor stars, the notable decrease in [O/Fe] (but small increase in [Na/Fe]) with increasing luminosity that affects primarily the "extreme" population, the small fraction of stars with halo-like composition, and the paucity of O-poor AGB stars. In agreement with recent work, we conclude that the most O-poor M13 giants are likely He-enriched and that most (all?) O-poor RGB stars evolve to become extreme HB and AGB-manqu\'e stars. In contrast, the "primordial" and "intermediate" population stars appear to experience standard HB and AGB evolution.
- ID:
- ivo://CDS.VizieR/J/A+AS/113/299
- Title:
- Abundances and velocities for cluster giants
- Short Name:
- J/A+AS/113/299
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a large dataset consisting of giants in the field, and in open and globular clusters. A total of 122 giants were observed in the fields of 8 open clusters. A total of 342 giants were observed in the fields of 25 globular clusters. A total of 36 field stars with well known abundances and luminosities were also observed. Table 8 lists the spectral indices measured for the giants observed with the Argus and Red Channel spectrographs during 1991 and 1992. The central and continuum passbands for these indices are defined in Table 6.
- ID:
- ivo://CDS.VizieR/J/AJ/152/21
- Title:
- Abundances for red giants in NGC 6342 and NGC 6366
- Short Name:
- J/AJ/152/21
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present radial velocities and chemical abundances for red giant branch stars in the Galactic bulge globular clusters NGC6342 and NGC6366. The velocities and abundances are based on measurements of high-resolution (R>~20000) spectra obtained with the MMT-Hectochelle and WIYN-Hydra spectrographs. We find that NGC6342 has a heliocentric radial velocity of +112.5km/s ({sigma}=8.6km/s), NGC6366 has a heliocentric radial velocity of -122.3km/s ({sigma}=1.5km/s), and both clusters have nearly identical metallicities ([Fe/H]~-0.55). NGC6366 shows evidence of a moderately extended O-Na anti-correlation, but more data are needed for NGC6342 to determine if this cluster also exhibits the typical O-Na relation likely found in all other Galactic globular clusters. The two clusters are distinguished from similar metallicity field stars as having larger [Na/Fe] spreads and enhanced [La/Fe] ratios, but we find that NGC6342 and NGC6366 display {alpha} and Fe-peak element abundance patterns that are typical of other metal-rich ([Fe/H]>-1) inner Galaxy clusters. However, the median [La/Fe] abundance may vary from cluster-to-cluster.
- ID:
- ivo://CDS.VizieR/J/A+A/506/729
- Title:
- Abundances in globular cluster Pal 3
- Short Name:
- J/A+A/506/729
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Chemical abundances of 25 alpha-, iron peak-, and neutron-capture elements in the remote (R=90kpc) outer halo globular cluster have been determined for 4 red giants observed with the Magellan/MIKE spectrograph and from integrated spectra of 19 stars obtained with the Keck/HIRES instrument. The resulting abundance ratios show that Pal 3 is very similar to globular clusters of the inner halo and very dissimilar from dwarf spheroidal galaxy stars. Its neutron capture element ratios are compatible with a pure r-process enrichment.
- ID:
- ivo://CDS.VizieR/J/A+A/326/1069
- Title:
- Abundances in globular clusters
- Short Name:
- J/A+A/326/1069
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Tables 5, 6, and 7 present details of the derived abundances for the stars observed in the globular clusters M2, M13, and M56, respectively. Table 9 gives the measured equivalent widths for the iron lines of the field stars. Table 10 gives the measured equivalent widths for the programme stars of this survey.
- ID:
- ivo://CDS.VizieR/J/AJ/120/1364
- Title:
- Abundances in M3 and M13
- Short Name:
- J/AJ/120/1364
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze high-resolution, high signal-to-noise ratio spectra of six red giant branch (RGB) stars in the globular cluster M3 (NGC 5272) and three in M13 (NGC 6205) that were obtained with the 4 m Mayall Telescope and echelle spectrometer on Kitt Peak. The spectra include lines of O, Na, Mg, Al, Si, Ca, Ti, V, Mn, Fe, and Ni. We also analyze the [Al/Fe] values of 96 RGB stars in M13 covering the brightest 3.5 mag, which include 66 measurements that were derived from moderate-resolution, low signal-to-noise ratio spectra obtained with the WIYN 3.5 m telescope and Hydra multiobject spectrograph, also on Kitt Peak.
- ID:
- ivo://CDS.VizieR/J/AJ/141/175
- Title:
- Abundances in M15 RGB/RHB stars
- Short Name:
- J/AJ/141/175
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The globular cluster M15 is unique in its display of star-to-star variations in the neutron-capture elements. Comprehensive abundance surveys have been previously conducted for handfuls of M15 red giant branch (RGB) and red horizontal branch (RHB) stars. No attempt has been made to perform a single, self-consistent analysis of these stars, which exhibit a wide range in atmospheric parameters. In the current effort, a new comparative abundance derivation is presented for three RGB and six RHB members of the cluster. The analysis employs an updated version of the line transfer code MOOG, which now appropriately treats coherent, isotropic scattering.
