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

M. Van Der Swaelmen, B. Barbuy, V. Hill, M. Zoccali, D. Minniti, S. Ortolani, A. Gómez

Resultado de la investigación: Article

22 Citas (Scopus)

Resumen

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. We obtained high-resolution spectra of our giant stars using the FLAMES-UVES spectrograph on the Very Large Telescope. We inspected four bulge fields along the minor axis. Results. We measure the chemical evolution of heavy elements, as a function of metallicity, in the Galactic bulge. Conclusions. The [Ba,La,Ce,Nd/Fe] vs. [Fe/H] ratios decrease with increasing metallicity, in which aspect they differ from disc stars. In our metal-poor bulge stars, La and Ba are enhanced relative to their thick disc counterpart, while in our metal-rich bulge stars La and Ba are underabundant relative to their disc counterpart. Therefore, this contrast between bulge and discs trends indicates that bulge and (solar neighbourhood) thick disc stars could behave differently. An increase in [La,Nd/Eu] with increasing metallicity, for metal-rich stars with [Fe/H] > 0 dex, may indicate that the s-process from AGB stars starts to operate at a metallicity around solar. Finally, [Eu/Fe] follows the [α/Fe] behaviour, as expected, since these elements are produced by SNe type II.

Idioma originalEnglish
Número de artículoA1
PublicaciónAstronomy and Astrophysics
Volumen586
DOI
EstadoPublished - 1 feb 2016

Huella dactilar

galactic bulge
heavy elements
metallicity
stars
metal
metals
giant stars
solar neighborhood
asymptotic giant branch stars
chemical evolution
clumps
spectrographs
telescopes
trends
high resolution

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Citar esto

Van Der Swaelmen, M., Barbuy, B., Hill, V., Zoccali, M., Minniti, D., Ortolani, S., & Gómez, A. (2016). Heavy elements Ba, La, Ce, Nd, and Eu in 56 Galactic bulge red giants. Astronomy and Astrophysics, 586, [A1]. https://doi.org/10.1051/0004-6361/201525709
Van Der Swaelmen, M. ; Barbuy, B. ; Hill, V. ; Zoccali, M. ; Minniti, D. ; Ortolani, S. ; Gómez, A. / Heavy elements Ba, La, Ce, Nd, and Eu in 56 Galactic bulge red giants. En: Astronomy and Astrophysics. 2016 ; Vol. 586.
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abstract = "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. We obtained high-resolution spectra of our giant stars using the FLAMES-UVES spectrograph on the Very Large Telescope. We inspected four bulge fields along the minor axis. Results. We measure the chemical evolution of heavy elements, as a function of metallicity, in the Galactic bulge. Conclusions. The [Ba,La,Ce,Nd/Fe] vs. [Fe/H] ratios decrease with increasing metallicity, in which aspect they differ from disc stars. In our metal-poor bulge stars, La and Ba are enhanced relative to their thick disc counterpart, while in our metal-rich bulge stars La and Ba are underabundant relative to their disc counterpart. Therefore, this contrast between bulge and discs trends indicates that bulge and (solar neighbourhood) thick disc stars could behave differently. An increase in [La,Nd/Eu] with increasing metallicity, for metal-rich stars with [Fe/H] > 0 dex, may indicate that the s-process from AGB stars starts to operate at a metallicity around solar. Finally, [Eu/Fe] follows the [α/Fe] behaviour, as expected, since these elements are produced by SNe type II.",
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Van Der Swaelmen, M, Barbuy, B, Hill, V, Zoccali, M, Minniti, D, Ortolani, S & Gómez, A 2016, 'Heavy elements Ba, La, Ce, Nd, and Eu in 56 Galactic bulge red giants', Astronomy and Astrophysics, vol. 586, A1. https://doi.org/10.1051/0004-6361/201525709

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.; Gómez, A.

En: Astronomy and Astrophysics, Vol. 586, A1, 01.02.2016.

Resultado de la investigación: Article

TY - JOUR

T1 - Heavy elements Ba, La, Ce, Nd, and Eu in 56 Galactic bulge red giants

AU - Van Der Swaelmen, M.

AU - Barbuy, B.

AU - Hill, V.

AU - Zoccali, M.

AU - Minniti, D.

AU - Ortolani, S.

AU - Gómez, A.

PY - 2016/2/1

Y1 - 2016/2/1

N2 - 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. We obtained high-resolution spectra of our giant stars using the FLAMES-UVES spectrograph on the Very Large Telescope. We inspected four bulge fields along the minor axis. Results. We measure the chemical evolution of heavy elements, as a function of metallicity, in the Galactic bulge. Conclusions. The [Ba,La,Ce,Nd/Fe] vs. [Fe/H] ratios decrease with increasing metallicity, in which aspect they differ from disc stars. In our metal-poor bulge stars, La and Ba are enhanced relative to their thick disc counterpart, while in our metal-rich bulge stars La and Ba are underabundant relative to their disc counterpart. Therefore, this contrast between bulge and discs trends indicates that bulge and (solar neighbourhood) thick disc stars could behave differently. An increase in [La,Nd/Eu] with increasing metallicity, for metal-rich stars with [Fe/H] > 0 dex, may indicate that the s-process from AGB stars starts to operate at a metallicity around solar. Finally, [Eu/Fe] follows the [α/Fe] behaviour, as expected, since these elements are produced by SNe type II.

AB - 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. We obtained high-resolution spectra of our giant stars using the FLAMES-UVES spectrograph on the Very Large Telescope. We inspected four bulge fields along the minor axis. Results. We measure the chemical evolution of heavy elements, as a function of metallicity, in the Galactic bulge. Conclusions. The [Ba,La,Ce,Nd/Fe] vs. [Fe/H] ratios decrease with increasing metallicity, in which aspect they differ from disc stars. In our metal-poor bulge stars, La and Ba are enhanced relative to their thick disc counterpart, while in our metal-rich bulge stars La and Ba are underabundant relative to their disc counterpart. Therefore, this contrast between bulge and discs trends indicates that bulge and (solar neighbourhood) thick disc stars could behave differently. An increase in [La,Nd/Eu] with increasing metallicity, for metal-rich stars with [Fe/H] > 0 dex, may indicate that the s-process from AGB stars starts to operate at a metallicity around solar. Finally, [Eu/Fe] follows the [α/Fe] behaviour, as expected, since these elements are produced by SNe type II.

KW - Galaxy: bulge

KW - Stars: abundances

KW - Stars: atmospheres

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DO - 10.1051/0004-6361/201525709

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