J/ApJ/645/613 Abundances of HD 221170 (Ivans+, 2006) ================================================================================ Near-ultraviolet observations of HD 221170: new insights into the nature of r-process-rich stars. Ivans I.I., Simmerer J., Sneden C., Lawler J.E., Cowan J.J., Gallino R., Bisterzo S. =2006ApJ...645..613I ================================================================================ ADC_Keywords: Stars, variable ; Abundances Keywords: Galaxy: abundances - Galaxy: evolution - nuclear reactions, nucleosynthesis, abundances - stars: abundances - stars: individual (HD 221170) - stars: Population II Abstract: Employing high-resolution spectra obtained with the near-UV-sensitive detector on the Keck I HIRES, supplemented by data obtained with the McDonald Observatory 2d-coude, we have performed a comprehensive chemical composition analysis of the bright r-process-rich metal-poor red giant star HD 221170. Analysis of 57 individual neutral and ionized species yielded abundances for a total of 46 elements and significant upper limits for an additional five. Model stellar atmosphere parameters were derived with the aid of ~200 Fe peak transitions. From more than 350 transitions of 35 neutron-capture (Z>30) species, abundances for 30 neutron-capture elements and upper limits for three others were derived. Utilizing 36 transitions of La, 16 of Eu, and seven of Th, we derive ratios of log{epsilon}(Th/La)=-0.73 ({sigma}=0.06) and log{epsilon}(Th/Eu)=-0.60 ({sigma}=0.05), values in excellent agreement with those previously derived for other r-process-rich metal-poor stars such as CS 22892-052, BD +17 3248, and HD 115444. Based on the Th/Eu chronometer, the inferred age is 11.7+/-2.8Gyr. The abundance distribution of the heavier neutron-capture elements (Z>=56) is fitted well by the predicted scaled solar system r-process abundances, as also seen in other r-process-rich stars. Unlike other r-process-rich stars, however, we find that the abundances of the lighter neutron-capture elements (37] with <[Fe/H]>=-2.18. Note (4): Notes as follows: HFS = Denotes a feature for which hyperfine structure splitting was accounted for. iso = Denotes a feature for which isotopic splitting was accounted for. d = Excluded from analysis (non-negligible non-LTE correction required). e = Hyperfine structure not considered for EW<30m{AA}. f = Excluded from analysis (HFS information unavailable for non-negligible HFS correction). limit = upper limit for log(e) and [X/Fe]. -------------------------------------------------------------------------------- Byte-by-byte Description of file: table2.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 8 F8.3 0.1nm Wave Wavelength in Angstroms 10- 14 A5 --- Species Species Identification 16- 20 F5.3 eV ExtPot Excitation Potential 22- 27 F6.3 [-] log(gf) Log of the Oscillator Strength (1) -------------------------------------------------------------------------------- Note (1): Hyperfine structure information adopted from Kurucz & Bell (1995, Kurucz CD-ROM 23, Atomic Line Data (Cambridge: SAO)), with log(gf)'s normalized to those adopted in this study (see Section 3). -------------------------------------------------------------------------------- Byte-by-byte Description of file: table4.dat table6.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 9 F9.3 cm-1 WaveNum Center-of-Gravity Wavenumber 11- 19 F9.4 0.1nm Wave Center-of-Gravity Wavelength in Angstroms 21- 23 F3.1 --- Fup Component upper F or total angular momentum 25- 27 F3.1 --- Flow Component lower F or total angular momentum 29- 36 F8.5 cm-1 CWaveNum Component offset wavenumber wrt Center-of-gravity Wavenumber 38- 46 F9.6 0.1nm CWave Component offset Wavelength wrt Center-of-gravity Wavelength in Angstroms 48- 54 F7.5 --- Str Component strength (1) -------------------------------------------------------------------------------- Note (1): Normalized to sum to one. -------------------------------------------------------------------------------- History: From electronic version of the journal ================================================================================ (End) Greg Schwarz [AAS], Patricia Vannier [CDS] 02-Oct-2007