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J/ApJ/838/44    Abundances of the brightest member of Tuc III    (Hansen+, 2017)

An r-process enhanced star in the dwarf galaxy Tucana III. Hansen T.T., Simon J.D., Marshall J.L., Li T.S., Carollo D., Depoy D.L., Nagasawa D.Q., Bernstein R.A., Drlica-Wagner A., Abdalla F.B., Allam S., Annis J., Bechtol K., Benoit-Levy A., Brooks D., Buckley-Geer E., Carnero Rosell A., Carrasco Kind M., Carretero J., Cunha C.E., da Costa L.N., Desai S., Eifler T.F., Fausti Neto A., Flaugher B., Frieman J., Garcia-Bellido J., Gaztanaga E., Gerdes D.W., Gruen D., Gruendl R.A., Gschwend J., Gutierrez G., James D.J., Krause E., Kuehn K., Kuropatkin N., Lahav O., Miquel R., Plazas A.A., Romer A.K., Sanchez E., Santiago B., Scarpine V., Smith R.C., Soares-Santos M., Sobreira F., Suchyta E., Swanson M.E.C., Tarle G., Walker A.R., (the DES Collaboration) <Astrophys. J., 838, 44-44 (2017)> =2017ApJ...838...44H (SIMBAD/NED BibCode)
ADC_Keywords: Abundances ; Equivalent widths ; Stars, peculiar Keywords: galaxies: abundances; galaxies: dwarf; stars: abundances; stars: chemically peculiar Abstract: Chemically peculiar stars in dwarf galaxies provide a window for exploring the birth environment of stars with varying chemical enrichment. We present a chemical abundance analysis of the brightest star in the newly discovered ultra-faint dwarf galaxy candidate TucanaIII. Because it is particularly bright for a star in an ultra-faint Milky Way (MW) satellite, we are able to measure the abundance of 28 elements, including 13 neutron-capture species. This star, DESJ235532.66-593114.9 (DES J235532), shows a mild enhancement in neutron-capture elements associated with the r-process and can be classified as an r-I star. DES J235532 is the first r-I star to be discovered in an ultra-faint satellite, and Tuc III is the second extremely low-luminosity system found to contain r-process enriched material, after Reticulum II. Comparison of the abundance pattern of DES J235532 with r-I and r-II stars found in other dwarf galaxies and in the MW halo suggests a common astrophysical origin for the neutron-capture elements seen in all r-process enhanced stars. We explore both internal and external scenarios for the r-process enrichment of Tuc III and show that with abundance patterns for additional stars, it should be possible to distinguish between them. Description: We observed DES J235532.66-593114.9 with the MIKE spectrograph on the Magellan/Clay telescope on the night of 2015 August 14. We obtained a total of 3.5hr of integration time (R=28000 on the blue channel and R=22000 on the red channel). Objects: ------------------------------------------------------------------- RA (ICRS) DE Designation(s) ------------------------------------------------------------------- 23 55 32.80 -59 31 12.0 DES J235532 = DES J235532.66-593114.9 ------------------------------------------------------------------- File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 36 145 Fe I and Fe II lines used for parameter determination table2.dat 24 126 Atomic line data
See also: J/ApJ/612/447 : Draco 119 and HD 88609 equivalent widths (Fulbright+, 2004) J/ApJ/617/1091 : La and Eu abundances in 85 stars (Simmerer+, 2004) J/A+A/439/129 : HERES II. Spectroscopic analysis (Barklem+, 2005) J/ApJ/655/492 : Equivalent widths of 26 metal-poor stars (Aoki+, 2007) J/ApJ/701/1053 : Abundances of 8 stars in the Draco dSph (Cohen+, 2009) J/ApJ/719/931 : Chemical evolution of the UMi dSph (Cohen+, 2010) J/A+A/523/A17 : Individual stars in Fornax dSph center (Letarte+, 2010) J/ApJ/742/37 : Abundances of six RGB stars in M22 (Roederer+, 2011) J/AJ/141/175 : Abundances in M15 RGB/RHB stars (Sobeck+, 2011) J/AJ/144/168 : Spectroscopy of Scl 1019417 and UMi 20103 (Kirby+, 2012) J/ApJ/751/102 : Equivalent widths of 9 RGB in Carina dSph (Venn+, 2012) J/ApJ/769/57 : Equivalent widths of metal-poor stars (Frebel+, 2013) J/ApJ/775/L27 : Chemical abundances in a metal-poor RGB star (Johnson+, 2013) J/ApJ/778/149 : Abundances for 3 stars in Sgr dSph (McWilliam+, 2013) J/ApJ/764/78 : Oxygen abundances in nearby FGK stars (Ramirez+, 2013) J/A+A/572/A88 : Measured EWs for Fornax RGB stars (Lemasle+, 2014) J/A+A/571/A47 : Linelist of CH in stellar atmospheres (Masseron+, 2014) J/ApJ/797/21 : Carbon-enhanced metal-poor stars (Placco+, 2014) J/AJ/147/136 : Stars of very low metal abundance. VI. (Roederer+, 2014) J/ApJ/802/93 : Abundance analysis of 5 stars in Sculptor (Simon+, 2015) J/A+A/574/A129 : The First CEMP star in the Sculptor dSph (Skuladottir+, 2015) J/ApJ/830/93 : Ret II brightest red giant member abundances (Ji+, 2016) J/ApJ/838/11 : Member stars in the MW satellite Tucana III (Simon+, 2017) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 5 A5 --- Species Species 7- 13 F7.2 0.1nm lambda [3743.3/6750.2] Species wavelength, Angstroms 15- 18 F4.2 eV ExPot [0/4.5] Excitation potential 20- 25 F6.3 [-] log(gf) [-5/0.6] Log of the oscillator strength 27- 31 F5.1 10-13m EW [10/215.5] Equivalent Width, Species, milli-Angstroms 33- 36 F4.2 [-] logeps [4.7/5.7] Log ε abundance
Byte-by-byte Description of file: table2.dat
Bytes Format Units Label Explanations
1- 5 A5 --- Species Species 7- 13 F7.2 0.1nm lambda [3768.4/7699] Species wavelength, Angstroms 15- 18 F4.2 eV ExPot [0/4.4] Excitation potential 20- 24 F5.2 [-] log(gf) [-9.8/0.6] Log of the oscillator strength
History: From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 26-Oct-2017
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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