TY - JOUR
T1 - VLT-UVES analysis of 5 giants in 47 Tucanae
AU - Alves-Brito, A.
AU - Barbuy, B.
AU - Ortolani, S.
AU - Momany, Y.
AU - Hill, V.
AU - Zoccali, M.
AU - Renzini, A.
AU - Minniti, D.
AU - Pasquini, L.
AU - Bica, E.
AU - Rich, R. M.
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2005/5
Y1 - 2005/5
N2 - High resolution spectra of 5 giants, including a horizontal branch star, of the metal-rich globular cluster 47 Tucanae were obtained with the UVES spectrograph at the 8 m VLT UT2-Kueyen telescope. The atmospheric parameters (Teff, log g, [Fe/H], vt) were derived from VIJK photometry and spectroscopic data based on FeI and FeII lines. FeI and FeII iron abundances and respective total errors [Fe I/H] = -0.66 ± 0.12 and [Fe II/H] = -0.69 ± 0.24 are found. Abundances of α (O, Mg, Ca, Si, Ti), odd-Z (Na, Al), s- (Ba, La, Zr), and r-process (Eu) elements were determined by means of spectrum synthesis. The main results are [O/Fe] = +0.35 ± 0.11, [Mg/Fe] ≈ [Si/Fe] ≈ [Ti/Fe] = +0.23 ± 0.17, [Ca/Fe] = 0.0 ± 0.15, [Ba/Fe] = +0.31 ± 0.22 and [Eu/Fe] = +0.33 ± 0.10. Overabundances of the α-elements O, Mg, Si and Ti, and of Eu are similar to those seen in halo metal-poor stars, whereas a solar Ca-to-Fe ratio resembles the values found in bulge stars. An overall metallicity Z = 0.006 or [M/H] =-0.45 is thus obtained, as is a mean heliocentric radial velocity v rhel = -22.43 ± 1.99 kms-1.
AB - High resolution spectra of 5 giants, including a horizontal branch star, of the metal-rich globular cluster 47 Tucanae were obtained with the UVES spectrograph at the 8 m VLT UT2-Kueyen telescope. The atmospheric parameters (Teff, log g, [Fe/H], vt) were derived from VIJK photometry and spectroscopic data based on FeI and FeII lines. FeI and FeII iron abundances and respective total errors [Fe I/H] = -0.66 ± 0.12 and [Fe II/H] = -0.69 ± 0.24 are found. Abundances of α (O, Mg, Ca, Si, Ti), odd-Z (Na, Al), s- (Ba, La, Zr), and r-process (Eu) elements were determined by means of spectrum synthesis. The main results are [O/Fe] = +0.35 ± 0.11, [Mg/Fe] ≈ [Si/Fe] ≈ [Ti/Fe] = +0.23 ± 0.17, [Ca/Fe] = 0.0 ± 0.15, [Ba/Fe] = +0.31 ± 0.22 and [Eu/Fe] = +0.33 ± 0.10. Overabundances of the α-elements O, Mg, Si and Ti, and of Eu are similar to those seen in halo metal-poor stars, whereas a solar Ca-to-Fe ratio resembles the values found in bulge stars. An overall metallicity Z = 0.006 or [M/H] =-0.45 is thus obtained, as is a mean heliocentric radial velocity v rhel = -22.43 ± 1.99 kms-1.
KW - Globular clusters: general
KW - Globular clusters: individual: 47 Tucanae
KW - Stars: abundances
UR - http://www.scopus.com/inward/record.url?scp=20844457450&partnerID=8YFLogxK
U2 - 10.1051/0004-6361:20041634
DO - 10.1051/0004-6361:20041634
M3 - Article
AN - SCOPUS:20844457450
SN - 0004-6361
VL - 435
SP - 657
EP - 667
JO - Astronomy and Astrophysics
JF - Astronomy and Astrophysics
IS - 2
ER -