Distribution Of The Whole Element Abundances In Metal-poor Stars

The metal-poor stars are known as the stellar evolution history of the "fossil." Studying the nucleosynthesis element abundances to test nucleosynthesis theories and exploration of star formation have great significance. S-process theory has been relatively well, but the understanding of r-process are relatively vague.In this paper, based on element nucleosynthesis theory, using parametric method to divide r-process into a weak r-process and a main r-process. Predict from a theoretical point to view for the element abundances, and explore the distribution of element abundances characteristics and laws,so as to further discuss the r-process nucleosynthesis process and the possible site. This article use HD 122563 and CS 22892-001 as a typical star of weak r-process and main r-process.The way is using the least square method to find the smallest prescribing . 98 r-process enhancde metal-poor stars were calculated to predict the abundance of their elements. And the error is detailed into metal-poor stars observation error and the typical satellite observation error, so that our model for maximum optimization. By calculating the metal-poor stars to study two composition of r-process. Parameterized model is the specific physical processes mathematically, and these two processes supported by two-component coefficients.Thus can see intuitively the proportion of the weak and main r-process in the r-process.By this calculation, the accuracy of our model can be intuitively seen from the figure. Thus the weak and main r-process of we mading is quite credible.R- process is closely linked with formation and evolution of the star. Through the study of nuclear synthesis, we can understand the origin of elements, star formation and chemical evolution of galaxies. In recent years, study of the r-process nuclear synthesis on metal-poor stars are more and more。However, there does not have a mature theory so far, and there are also lot of controversy on place of their formation . Therefore, the work for the r-process of this article, as well as for the nucleosynthesis of the studies have very important significance.