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Related papers: NGC5694: another extra-galactic globular cluster

200 papers

Chemical abundances of six extremely metal-poor ([Fe/H]<-2.5) stars in the Sextans dwarf spheroidal galaxy are determined based on high resolution spectroscopy (R=40,000) with the Subaru Telescope High Dispersion Spectrograph. (1) The Fe…

Detailed elemental-abundance patterns of giant stars in the Galactic halo measured by APOGEE-2 have revealed the existence of a unique and significant stellar sub-population of silicon-enhanced ([Si/Fe]$\gtrsim +0.5$) metal-poor stars,…

Astrophysics of Galaxies · Physics 2021-01-04 José G. Fernández-Trincado , Timothy C. Beers , Dante Minniti

We present a detailed abundance analysis based on high resolution and high signal-to-noise spectra of eight extremely metal poor (EMP) stars with [Fe/H] < -3.5$ dex, four of which are new. Only stars with 4900 < Teff< 5650 K are included.…

Recent studies of chemical abundances in metal-poor Halo stars show the existence of different populations, which is important for studies of Galaxy formation and evolution. Here we revisit the twin pair of chemically anomalous stars HD…

Solar and Stellar Astrophysics · Physics 2018-02-22 Henrique Reggiani , Jorge Meléndez

AIMS. In this paper we present the chemical abundance analysis from high resolution UVES spectra of seventeen bright giant stars of the Globular Cluster M~22. RESULTS. We obtained an average iron abundance of [Fe/H]=-1.76\pm0.02 (internal…

Solar and Stellar Astrophysics · Physics 2015-05-13 A. F. Marino , A. P. Milone , G. Piotto , S. Villanova , L. R. Bedin , A. Bellini , A. Renzini

We report the results of a coherent study of three chemically anomalous metal-poor ([Fe/H] ~ -2) stars. These objects exhibit unusually low abundances of Mg, Si, Ca (alpha-elements) and Sr, Y, and Ba (neutron-capture elements). Our analyses…

We observed 6 He-clump stars of the intermediate-age stellar cluster Gaia1 with the MIKE/MAGELLAN spectrograph. A possible extra-galactic origin of this cluster, recently discovered thanks to the first data release of the ESA Gaia mission,…

Solar and Stellar Astrophysics · Physics 2017-07-26 A. Mucciarelli , L. Monaco , P. Bonifacio , I. Saviane

NGC 362 is a non-common Type II Galactic globular cluster, showing a complex pseudo two-color diagram or 'chromosome map'. The clear separation of its stellar populations in the color-magnitude diagram and the distribution of the giant…

Astrophysics of Galaxies · Physics 2022-07-13 C. Vargas , S. Villanova , D. Geisler , C. Muñoz , L. Monaco , J. O'Connell , Ata Sarajedini

Context: Chemical element abundances for distant Galactic globular clusters (GCs) hold important clues to the origin of the Milky Way halo and its substructures. Aims: We study the chemical composition of red giant stars in Pal 4 - one of…

Astrophysics of Galaxies · Physics 2015-05-18 Andreas Koch , Patrick Côté

We present chemical abundances for 17 elements in a sample of 11 red giant branch stars in NGC 6362 from UVES spectra. NGC 6362 is one of the least massive globulars where multiple populations have been detected, yet its detailed chemical…

Solar and Stellar Astrophysics · Physics 2017-04-12 D. Massari , A. Mucciarelli , E. Dalessandro , M. Bellazzini , S. Cassisi , G. Fiorentino , R. A. Ibata , C. Lardo , M. Salaris

We present radial velocities, stellar parameters, and detailed abundances of 39 elements derived from high-resolution spectroscopic observations of red giant stars in the luminous, metal-poor globular cluster NGC 5824. We observe 26 stars…

Solar and Stellar Astrophysics · Physics 2015-12-02 Ian U. Roederer , Mario Mateo , John I. Bailey , Meghin Spencer , Jeffrey D. Crane , Stephen A. Shectman

We derive abundance ratios for nine stars in the relatively high-metallicity bulge globular cluster NGC 6380. We find a mean cluster metallicity between [Fe/H]$= -0.80$ and $-0.73$, with no clear evidence for a variation in iron abundances…

We report the discovery of a unique collection of metal-poor giant-stars, that exhibit anomalously high levels of $^{28}$Si, clearly above typical Galactic levels. Our sample spans a narrow range of metallicities, peaking at $-1.07\pm…

We have compiled a sample of globular clusters with high quality stellar abundances from the literature to compare to the chemistries of stars in the Galaxy and those in dwarf spheroidal galaxies. Of the 45 globular clusters examined, 29…

Astrophysics · Physics 2008-11-26 Barton J. Pritzl , Kim A. Venn , Mike J. Irwin

We analyze a high-resolution, high signal-to-noise spectrum of the carbon-rich, extremely metal-poor star CS29498-043, obtained with the Subaru Telescope High Dispersion Spectrograph. We find its iron abundance is extremely low ([Fe/H] =…

Astrophysics · Physics 2009-11-07 W. Aoki , J. E. Norris , S. G. Ryan , T. C. Beers , H. Ando

We have observed 15 red giant stars in the relatively massive, metal-poor globular cluster NGC 4833 using the Magellan Inamori Kyocera Echelle spectrograph at Magellan. We calculate stellar parameters for each star and perform a standard…

Solar and Stellar Astrophysics · Physics 2015-06-24 Ian U. Roederer , Ian B. Thompson

Spectra of unevolved metal-poor halo stars uniquely reflect the elemental abundances incorporated during the earliest Galactic epoch. Their heavy-element content is well understood as the products of neutron capture on iron-peak elements.…

Solar and Stellar Astrophysics · Physics 2020-07-01 R. C. Peterson , B. Barbuy , M. Spite

Recent observations have shown that a growing number of the most massive Galactic globular clusters contain multiple populations of stars with different [Fe/H] and neutron-capture element abundances. NGC 6273 has only recently been…

VLT-UVES high resolution spectra of seven turnoff stars in the metal-poor globular cluster NGC 6397 have been obtained. Atmospheric parameters and abundances of several elements (Li, Na, Mg, Ca, Sc, Ti, Cr, Fe, Ni, Zn and Ba) were derived…

NGC 2419 is a peculiar Galactic globular cluster in terms of size/luminosity, and chemical abundance anomalies. Here, we present Str\"omgren $uvby$ photometry of the cluster. Using the gravity- and metallicity-sensitive $c_1$ and $m_1$…

Astrophysics of Galaxies · Physics 2015-10-12 Matthias J. Frank , Andreas Koch , Sofia Feltzing , Nikolay Kacharov , Mark I. Wilkinson , Mike Irwin