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Context. Extremely metal-poor (EMP) stars provide us with indirect information on the first generations of massive stars. The TOPoS survey has been designed to increase the census of these stars and to provide a chemical inventory that is as detailed as possible. Aims. Seven of the most iron-poor...


Bonifacio, P.Caffau, E.Spite, M.Spite, F.Sbordone, L.Monaco, L.François, P.Plez, B.Molaro, P.Gallagher, A.J.Cayrel, R.Christlieb, N.Klessen, R.S.Koch, A.Ludwig, H.-G.Steffen, M.Zaggia, S.Abate, C.[TOPoS: IV. Chemical abundances from high-resolution observations of seven extremely metal-poor stars]TOPoS: IV. Chemical abundances from high-resolution observations of seven extremely metal-poor stars

Context. The ratio of the first overtone (1O)/fundamental (F) periods of mixed-mode Cepheids that pulsate simultaneously in these two modes (F/1O) is metallicity-dependent. It can therefore be used to characterize the systems that host such variable stars. Aims. We want to take advantage of the F...


Lemasle, B.Hajdu, G.Kovtyukh, V.Inno, L.Grebel, E.K.Catelan, M.Bono, G.François, P.Kniazev, A.Da Silva, R.Storm, J.[Milky Way metallicity gradient from Gaia DR2 F/1O double-mode Cepheids]Milky Way metallicity gradient from Gaia DR2 F/1O double-mode Cepheids

Context. Globular clusters are known to host multiple stellar populations, which are a signature of their formation process. The globular cluster E3 is one of the few low-mass globulars that is thought not to host multiple populations. Aims. We investigate red giant branch stars in E3 with the ai...


Monaco, L.Villanova, S.Carraro, G.Mucciarelli, A.Moni Bidin, C.[Chemical abundance analysis of red giant branch stars in the globular cluster E3]Chemical abundance analysis of red giant branch stars in the globular cluster E3

Sagittarius (Sgr) is a massive disrupted dwarf spheroidal galaxy in the Milky Way halo that has undergone several stripping events. Previous chemical studies were restricted mainly to a few, metal-rich ([Fe/H] ) stars that suggested a top-light initial mass function (IMF). Here we present the fir...


Hansen, C.J.El-Souri, M.Monaco, L.Villanova, S.Bonifacio, P.Caffau, E.Sbordone, L.[Ages and Heavy Element Abundances from Very Metal-poor Stars in the Sagittarius Dwarf Galaxy]Ages and Heavy Element Abundances from Very Metal-poor Stars in the Sagittarius Dwarf Galaxy

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 to better understand their star formation and chemical evolution. Aims. We r...


François, P.Monaco, L.Bonifacio, P.Moni Bidin, C.Geisler, D.[Abundance ratios of red giants in low-mass ultra-faint dwarf spheroidal galaxies]Abundance ratios of red giants in low-mass ultra-faint dwarf spheroidal galaxies

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 (BHB) and a metallicity of [Fe/H] ≈ −1.0. This means that it probably is on...


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

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

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 cluster. We derive abundances of C, N, O, Na, Mg, Al, Si, Ca, Ti, Cr, Fe, N...


Villanova, S.Monaco, L.Moni Bidin, C.Assmann, P.[A spectroscopic study of the globular Cluster NGC 4147]A spectroscopic study of the globular Cluster NGC 4147

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 by the Apache Point Observatory Galactic Evolution Experiment ( APOGEE), as ...


Fernandez-Alvar, ECarigi, LPrieto, CAHayden, MRBeers, TCFernandez-Trincado, JGMeza, ASchultheis, MSantiago, BXQueiroz, ABAnders, Fda Costa, LNChiappini, C[Chemical trends in the Galactic halo from APOGEE data]Chemical trends in the Galactic halo from APOGEE data

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, but the high optical extinction in this region has prevented extensive resear...


Tang, BCohen, REGeisler, DSchiavon, RPMajewski, SRVillanova, SCarrera, RZamora, OGarcia-Hernandez, DAShetrone, MFrinchaboy, PMeza, AFernandez-Trincado, JGMunoz, RRLin, CCLane, RRNitschelm, CPan, KBizyaev, DOravetz, DSimmons, A[Two groups of red giants with distinct chemical abundances in the bulge globular cluster NGC 6553 through the eyes of APOGEE]Two groups of red giants with distinct chemical abundances in the bulge globular cluster NGC 6553 through the eyes of APOGEE

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