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TOPoS: III. An ultra iron-poor CEMP multiple system

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TOPoS: III. An ultra iron-poor CEMP multiple system. / Caffau, E.; Bonifacio, P.; Spite, M. et al.
In: Astronomy and Astrophysics, Vol. 595, L6, 11.2016.

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Harvard

Caffau, E, Bonifacio, P, Spite, M, Spite, F, Monaco, L, Sbordone, L, Francois, P, Gallagher, A, Plez, B, Zaggia, S, Ludwig, H-G, Cayrel, R, Koch, A, Steffen, M, Salvadori, S, Klessen, RS, Glover, S & Christlieb, N 2016, 'TOPoS: III. An ultra iron-poor CEMP multiple system', Astronomy and Astrophysics, vol. 595, L6. https://doi.org/10.1051/0004-6361/201629776

APA

Caffau, E., Bonifacio, P., Spite, M., Spite, F., Monaco, L., Sbordone, L., Francois, P., Gallagher, A., Plez, B., Zaggia, S., Ludwig, H-G., Cayrel, R., Koch, A., Steffen, M., Salvadori, S., Klessen, R. S., Glover, S., & Christlieb, N. (2016). TOPoS: III. An ultra iron-poor CEMP multiple system. Astronomy and Astrophysics, 595, Article L6. https://doi.org/10.1051/0004-6361/201629776

Vancouver

Caffau E, Bonifacio P, Spite M, Spite F, Monaco L, Sbordone L et al. TOPoS: III. An ultra iron-poor CEMP multiple system. Astronomy and Astrophysics. 2016 Nov;595:L6. Epub 2016 Oct 12. doi: 10.1051/0004-6361/201629776

Author

Caffau, E. ; Bonifacio, P. ; Spite, M. et al. / TOPoS: III. An ultra iron-poor CEMP multiple system. In: Astronomy and Astrophysics. 2016 ; Vol. 595.

Bibtex

@article{92fc5ed6007d4cc69409093138b99f11,
title = "TOPoS: III. An ultra iron-poor CEMP multiple system",
abstract = "Aims. One of the primary objectives of the TOPoS survey is to search for the most metal-poor stars. Our search has led to the discovery of one of the most iron-poor objects known, SDSS J092912.32+023817.0. This object is a multiple system, in which two components are clearly detected in the spectrum. Methods. We have analysed 16 high-resolution spectra obtained using the UVES spectrograph at the ESO 8.2 m VLT telescope to measure radial velocities and determine the chemical composition of the system. Results. Cross correlation of the spectra with a synthetic template yields a double-peaked cross-correlation function (CCF) for eight spectra, and in one case there is evidence for the presence of a third peak. Chemical analysis of the spectrum obtained by averaging all the spectra for which the CCF showed a single peak found that the iron abundance is [Fe/H]=–4.97. The system is also carbon enhanced with [C/Fe]=+3.91 (A(C) = 7.44). From the permitted oxygen triplet we determined an upper limit for oxygen of [O/Fe]< +3.52 such that C/O > 1.3. We are also able to provide more stringent upper limits on the Sr and Ba abundances ([Sr/Fe] < +0.70, and [Ba/Fe] < +1.46, respectively). ",
keywords = "stars: Population II, stars: abundances, stars: Population III, Galaxy: abundances, Galaxy: formation, Galaxy: halo",
author = "E. Caffau and P. Bonifacio and M. Spite and F. Spite and L. Monaco and L. Sbordone and P. Francois and A. Gallagher and B. Plez and S. Zaggia and H.-G. Ludwig and R. Cayrel and Andreas Koch and M. Steffen and S. Salvadori and R.S. Klessen and S. Glover and N. Christlieb",
year = "2016",
month = nov,
doi = "10.1051/0004-6361/201629776",
language = "English",
volume = "595",
journal = "Astronomy and Astrophysics",
issn = "1432-0746",
publisher = "EDP Sciences",

}

RIS

TY - JOUR

T1 - TOPoS: III. An ultra iron-poor CEMP multiple system

AU - Caffau, E.

AU - Bonifacio, P.

AU - Spite, M.

AU - Spite, F.

AU - Monaco, L.

AU - Sbordone, L.

AU - Francois, P.

AU - Gallagher, A.

AU - Plez, B.

AU - Zaggia, S.

AU - Ludwig, H.-G.

AU - Cayrel, R.

AU - Koch, Andreas

AU - Steffen, M.

AU - Salvadori, S.

AU - Klessen, R.S.

AU - Glover, S.

AU - Christlieb, N.

PY - 2016/11

Y1 - 2016/11

N2 - Aims. One of the primary objectives of the TOPoS survey is to search for the most metal-poor stars. Our search has led to the discovery of one of the most iron-poor objects known, SDSS J092912.32+023817.0. This object is a multiple system, in which two components are clearly detected in the spectrum. Methods. We have analysed 16 high-resolution spectra obtained using the UVES spectrograph at the ESO 8.2 m VLT telescope to measure radial velocities and determine the chemical composition of the system. Results. Cross correlation of the spectra with a synthetic template yields a double-peaked cross-correlation function (CCF) for eight spectra, and in one case there is evidence for the presence of a third peak. Chemical analysis of the spectrum obtained by averaging all the spectra for which the CCF showed a single peak found that the iron abundance is [Fe/H]=–4.97. The system is also carbon enhanced with [C/Fe]=+3.91 (A(C) = 7.44). From the permitted oxygen triplet we determined an upper limit for oxygen of [O/Fe]< +3.52 such that C/O > 1.3. We are also able to provide more stringent upper limits on the Sr and Ba abundances ([Sr/Fe] < +0.70, and [Ba/Fe] < +1.46, respectively). 

AB - Aims. One of the primary objectives of the TOPoS survey is to search for the most metal-poor stars. Our search has led to the discovery of one of the most iron-poor objects known, SDSS J092912.32+023817.0. This object is a multiple system, in which two components are clearly detected in the spectrum. Methods. We have analysed 16 high-resolution spectra obtained using the UVES spectrograph at the ESO 8.2 m VLT telescope to measure radial velocities and determine the chemical composition of the system. Results. Cross correlation of the spectra with a synthetic template yields a double-peaked cross-correlation function (CCF) for eight spectra, and in one case there is evidence for the presence of a third peak. Chemical analysis of the spectrum obtained by averaging all the spectra for which the CCF showed a single peak found that the iron abundance is [Fe/H]=–4.97. The system is also carbon enhanced with [C/Fe]=+3.91 (A(C) = 7.44). From the permitted oxygen triplet we determined an upper limit for oxygen of [O/Fe]< +3.52 such that C/O > 1.3. We are also able to provide more stringent upper limits on the Sr and Ba abundances ([Sr/Fe] < +0.70, and [Ba/Fe] < +1.46, respectively). 

KW - stars: Population II

KW - stars: abundances

KW - stars: Population III

KW - Galaxy: abundances

KW - Galaxy: formation

KW - Galaxy: halo

U2 - 10.1051/0004-6361/201629776

DO - 10.1051/0004-6361/201629776

M3 - Journal article

VL - 595

JO - Astronomy and Astrophysics

JF - Astronomy and Astrophysics

SN - 1432-0746

M1 - L6

ER -