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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 ...

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 ...

A spectroscopic study of the globular Cluster NGC 4147

Villanova, S.; Monaco, L.; Moni Bidin, C.; Assmann, P. (OXFORD UNIV PRESS, 2016-08)

We present the abundance analysis for a sample of 18 red giant branch stars in the metal-poor globular cluster NGC 4147 based on medium- and high-resolution spectra. This is the first extensive spectroscopic study of this ...

The Gaia-ESO Survey: Inhibited extra mixing in two giants of the open cluster Trumpler 20?

Smiljanic, R.; Franciosini, E.; Randich, S.; Magrini, L.; Bragaglia, A.; Pasquini, L.; Vallenari, A.; Tautvaišienė, G.; Biazzo, K.; Frasca, A.; Donati, P.; Delgado Mena, E.; Casey, A. R.; Geisler, D.; Villanova, S.; Tang, B.; Sousa, S. G.; Gilmore, G.; Bensby, T.; François, P.; Koposov, S. E.; Lanzafame, A. C.; Pancino, E.; Recio-Blanco, A.; Costado, M. T.; Hourihane, A.; Lardo, C.; de Laverny, P.; Lewis, J.; Monaco, L.; Morbidelli, L.; Sacco, G. G.; Worley, C. C.; Zaggia, S.; Martell, S. (EDP SCIENCES, 2016-06)

Aims. We report the discovery of two Li-rich giants, with A(Li) ~ 1.50, in an analysis of a sample of 40 giants of the open cluster Trumpler 20 (with turnoff mass ~1.8 M⊙). The cluster was observed in the context of the ...