E-viri
Recenzirano
Odprti dostop
-
Fernández-Trincado, José G.; Minniti, Dante; Beers, Timothy C.; Villanova, Sandro; Geisler, Doug; Souza, Stefano O.; Smith, Leigh C.; Placco, Vinicius M.; Vieira, Katherine; Pérez-Villegas, Angeles; Barbuy, Beatriz; Alves-Brito, Alan; Bidin, Christian Moni; Alonso-García, Javier; Tang, Baitian; Palma, Tali
Astronomy and astrophysics (Berlin), 11/2020, Letnik: 643Journal Article
The presence of nitrogen-enriched stars in globular clusters provides key evidence for multiple stellar populations (MPs), as has been demonstrated with globular cluster spectroscopic data towards the bulge, disk, and halo. In this work, we employ the VVV Infrared Astrometric Catalogue (VIRAC) and the DR16 SDSS-IV release of the APOGEE survey to provide the first detailed spectroscopic study of the bulge globular cluster UKS 1. Based on these data, a sample of six selected cluster members was studied. We find the mean metallicity of UKS 1 to be Fe/H = −0.98 ± 0.11, considerably more metal-poor than previously reported, and a negligible metallicity scatter, typical of that observed by APOGEE in other Galactic globular clusters. In addition, we find a mean radial velocity of 66.1 ± 12.9 km s −1 , which is in good agreement with literature values, within 1 σ . By selecting stars in the VIRAC catalogue towards UKS 1, we also measure a mean proper motion of ( μ α cos( δ ), μ δ ) = (−2.77 ± 0.23, −2.43 ± 0.16) mas yr −1 . We find strong evidence for the presence of MPs in UKS 1, since four out of the six giants analysed in this work have strong enrichment in nitrogen (N/Fe ≳ +0.95) accompanied by lower carbon abundances (C/Fe ≲ −0.2). Overall, the light- (C, N), α - (O, Mg, Si, Ca, Ti), Fe-peak (Fe, Ni), Odd-Z (Al, K), and the s -process (Ce, Nd, Yb) elemental abundances of our member candidates are consistent with those observed in globular clusters at similar metallicity. Furthermore, the overall star-to-star abundance scatter of elements exhibiting the multiple-population phenomenon in UKS 1 is typical of that found in other global clusters (GCs), and larger than the typical errors of some X/Fe abundances. Results from statistical isochrone fits in the VVV colour-magnitude diagrams indicate an age of 13.10 −1.29 +0.93 Gyr, suggesting that UKS 1 is a fossil relic in the Galactic bulge.
Avtor
![loading ... loading ...](themes/default/img/ajax-loading.gif)
Vnos na polico
Trajna povezava
- URL:
Faktor vpliva
Dostop do baze podatkov JCR je dovoljen samo uporabnikom iz Slovenije. Vaš trenutni IP-naslov ni na seznamu dovoljenih za dostop, zato je potrebna avtentikacija z ustreznim računom AAI.
Leto | Faktor vpliva | Izdaja | Kategorija | Razvrstitev | ||||
---|---|---|---|---|---|---|---|---|
JCR | SNIP | JCR | SNIP | JCR | SNIP | JCR | SNIP |
Baze podatkov, v katerih je revija indeksirana
Ime baze podatkov | Področje | Leto |
---|
Povezave do osebnih bibliografij avtorjev | Povezave do podatkov o raziskovalcih v sistemu SICRIS |
---|
Vir: Osebne bibliografije
in: SICRIS
To gradivo vam je dostopno v celotnem besedilu. Če kljub temu želite naročiti gradivo, kliknite gumb Nadaljuj.