Reanalysis of the Isotopic Mixture of Neutron-Capture Elements in the Metal-Poor Star HD 175305
ZHANG Jiang1,2,3**, WANG Bo1,2, ZHANG Bo4, HAN Zhan-Wen1,2
1National Astronomical Observatories/Yunnan Observatory, Chinese Academy of Sciences, Kunming 650011 2Key Laboratory for the Structure and Evolution of Celestial Objects, Chinese Academy of Sciences, Kunming 650011 3School of Mathematics and Science, Shijiazhuang University of Economics, Shijiazhuang 050016 4Department of Physics, Hebei Normal University, Shijiazhuang 050016
Reanalysis of the Isotopic Mixture of Neutron-Capture Elements in the Metal-Poor Star HD 175305
ZHANG Jiang1,2,3**, WANG Bo1,2, ZHANG Bo4, HAN Zhan-Wen1,2
1National Astronomical Observatories/Yunnan Observatory, Chinese Academy of Sciences, Kunming 650011 2Key Laboratory for the Structure and Evolution of Celestial Objects, Chinese Academy of Sciences, Kunming 650011 3School of Mathematics and Science, Shijiazhuang University of Economics, Shijiazhuang 050016 4Department of Physics, Hebei Normal University, Shijiazhuang 050016
摘要The neutron-capture process is traditionally postulated to be responsible for the nucleosynthesis of heavy elements beyond Fe. Based on the least squares method and solar isotopic abundances from the classical model, we estimate the relative contributions of the s- and r-processes to the abundance of neutron-capture elements in the metal-poor star HD 175305 from the component coefficients. Applying the calculated component coefficients Cr and Cs, the model predicts the isotopic fractions of elements Nd, Sm and Eu to be f142+144=0.482, f152+154=0.525 and f151=0.450, respectively. As well as the observed abundances, the isotropic fractions are also consistent with the calculations. Finally, for the first time, we estimated the contribution percentage of the two neutron processes (the r− and s-processes) from the observed isotopic fractions of different elements in HD 175305, e.g. an r-process contribution of 67%-32%+21% from the 4604 Å line of Sm.
Abstract：The neutron-capture process is traditionally postulated to be responsible for the nucleosynthesis of heavy elements beyond Fe. Based on the least squares method and solar isotopic abundances from the classical model, we estimate the relative contributions of the s- and r-processes to the abundance of neutron-capture elements in the metal-poor star HD 175305 from the component coefficients. Applying the calculated component coefficients Cr and Cs, the model predicts the isotopic fractions of elements Nd, Sm and Eu to be f142+144=0.482, f152+154=0.525 and f151=0.450, respectively. As well as the observed abundances, the isotropic fractions are also consistent with the calculations. Finally, for the first time, we estimated the contribution percentage of the two neutron processes (the r− and s-processes) from the observed isotopic fractions of different elements in HD 175305, e.g. an r-process contribution of 67%-32%+21% from the 4604 Å line of Sm.
ZHANG Jiang;**;WANG Bo;ZHANG Bo;HAN Zhan-Wen;. Reanalysis of the Isotopic Mixture of Neutron-Capture Elements in the Metal-Poor Star HD 175305[J]. 中国物理快报, 2012, 29(1): 19701-019701.
ZHANG Jiang, **, WANG Bo, ZHANG Bo, HAN Zhan-Wen,. Reanalysis of the Isotopic Mixture of Neutron-Capture Elements in the Metal-Poor Star HD 175305. Chin. Phys. Lett., 2012, 29(1): 19701-019701.
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