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Two groups of red giants with distinct chemical abundances in the bulge globular cluster NGC 6553 through the eyes of APOGEE

Tang, B; Cohen, RE; Geisler, D; Schiavon, RP; Majewski, SR; Villanova, S; Carrera, R; Zamora, O; Garcia-Hernandez, DA; Shetrone, M; Frinchaboy, P; Meza, A; Fernandez-Trincado, JG; Munoz, RR; Lin, CC; Lane, RR; Nitschelm, C; Pan, K; Bizyaev, D; Oravetz, D; Simmons, A (OXFORD UNIV PRESS, 2017-02)

Multiple populations revealed in globular clusters (GCs) are important windows to the formation and evolution of these stellar systems. The metal-rich GCs in the Galactic bulge are an indispensable part of this picture, ...

Chemical trends in the Galactic halo from APOGEE data

Fernandez-Alvar, E; Carigi, L; Prieto, CA; Hayden, MR; Beers, TC; Fernandez-Trincado, JG; Meza, A; Schultheis, M; Santiago, BX; Queiroz, AB; Anders, F; da Costa, LN; Chiappini, C (OXFORD UNIV PRESS, 2016-11)

The galaxy formation process in the A cold dark matter scenario can be constrained from the analysis of stars in the Milky Way's halo system. We examine the variation of chemical abundances in distant halo stars observed ...

Abundance ratios of red giants in low-mass ultra-faint dwarf spheroidal galaxies

François, P.; Monaco, L.; Bonifacio, P.; Moni Bidin, C.; Geisler, D. (EDP SCIENCES, 2016-04)

Context. Low-mass dwarf spheroidal galaxies are key objects for our understanding of the chemical evolution of the pristine Universe and the Local Group of galaxies. Abundance ratios in stars of these objects can be used ...

Chemical abundances of giant stars in NGC 5053 and NGC 5634, two globular clusters associated with the Sagittarius dwarf spheroidal galaxy?

Sbordone, L.; Monaco, L.; Moni Bidin, C.; Bonifacio, P.; Villanova, S.; Bellazzini, M.; Ibata, R.; Chiba, M.; Geisler, D.; Caffau, E.; Duffau, S. (EDP SCIENCES, 2015-07)

Context. The tidal disruption of the Sagittarius dwarf spheroidal galaxy (Sgr dSph) is producing the most prominent substructure in the Milky Way (MW) halo, the Sagittarius Stream. Aside from field stars, it is suspected ...

The Gaia-ESO Survey: Separating disk chemical substructures with cluster models⋆ Evidence of a separate evolution in the metal-poor thin disk

Rojas-Arriagada, A.; Recio-Blanco, A.; de Laverny, P.; Schultheis, M.; Guiglion, G.; Mikolaitis, Š.; Kordopatis, G.; Hill, V.; Gilmore, G.; Randich, S.; Alfaro, E. J.; Bensby, T.; Koposov, S. E.; Costado, M. T.; Franciosini, E.; Hourihane, A.; Jofré, P.; Lardo, C.; Lewis, J.; Lind, K.; Magrini, L.; Monaco, L.; Morbidelli, L.; Sacco, G. G.; Worley, C. C.; Zaggia, S.; Chiappini, C. (EDP SCIENCES, 2016-02)

Context. Recent spectroscopic surveys have begun to explore the Galactic disk system on the basis of large data samples, with spatial distributions sampling regions well outside the solar neighborhood. In this way, they ...

Heavy elements Ba, La, Ce, Nd, and Eu in 56 Galactic bulge red giants

Van der Swaelmen, M; Barbuy, B; Hill, V; Zoccali, M; Minniti, D; Ortolani, S; Gomez, A (EDP SCIENCES, 2016-02)

Aims. The aim of this work is the study of abundances of the heavy elements Ba, La, Ce, Nd, and Eu in 56 bulge giants (red giant branch and red clump) with metallicities ranging from 1 : 3 dex to 0 : 5 dex. Methods. ...

DISCOVERY OF A METAL-POOR FIELD GIANT WITH A GLOBULAR CLUSTER SECOND-GENERATION ABUNDANCE PATTERN

Fernandez-Trincado, JG; Robin, AC; Moreno, E; Schiavon, RP; Perez, AEG; Vieira, K; Cunha, K; Zamora, O; Sneden, C; Souto, D; Carrera, R; Johnson, JA; Shetrone, M; Zasowski, G; Garcia-Hernandez, DA; Majewski, SR; Reyle, C; Blanco-Cuaresma, S; Martinez-Medina, LA; Perez-Villegas, A; Valenzuela, O; Pichardo, B; Meza, A; Meszaros, S; Sobeck, J; Geisler, D; Anders, F; Schultheis, M; Tang, B; Roman-Lopes, A; Mennickent, RE; Pan, K; Nitschelm, C; Allard, F (IOP PUBLISHING, 2016-12)

We report on the detection, from observations obtained with the Apache Point Observatory Galactic Evolution Experiment spectroscopic survey, of a metal-poor ([Fe/H] = -1.3 dex) field giant star with an extreme Mg-Al abundance ...

High-resolution abundance analysis of red giants in the metal-poor bulge globular cluster HP 1

Barbuy, B.; Cantelli, E.; Vemado, A.; Ernandes, H.; Ortolani, S.; Saviane, I.; Bica, E.; Minniti, D.; Dias, B.; Momany, Y.; Hill, V.; Zoccali, M.; Siqueira-Mello, C. (EDP SCIENCES, 2016-06)

Context. The globular cluster HP 1 is projected at only 3.̊33 from the Galactic center. Together with its distance, this makes it one of the most central globular clusters in the Milky Way. It has a blue horizontal branch ...

Chemical composition of the stellar cluster Gaia1: No surprise behind Sirius

Mucciarelli, A.; Monaco, L.; Bonifacio, P.; Saviane, I. (EDP Sciences, 2017-07)

We observed six 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 ...

Disentangling the Galactic Halo with APOGEE. I. Chemical and Kinematical Investigation of Distinct Metal-poor Populations

Hayes, C.R.; Majewski, S.R.; Shetrone, M.; Fernández-Alvar, E.; Prieto, C.A.; Schuster, W.J.; Carigi, L.; Cunha, K.; Smith, V.V.; Sobeck, J.; Almeida, A.; Beers, T.C.; Carrera, R.; Fernández-Trincado, J.G.; García-Hernández, D.A.; Geisler, D.; Lane, R.R.; Lucatello, S.; Matthews, A.M.; Minniti, D.; Nitschelm, C.; Tang, B.; Tissera, P.B.; Zamora, O. (Institute of Physics Publishing, 2018)

We find two chemically distinct populations separated relatively cleanly in the [Fe/H]-[Mg/Fe] plane, but also distinguished in other chemical planes, among metal-poor stars (primarily with metallicities [Fe H] < -0.9) ...