Feasibility of determining surface of matter density distributions of nuclei at RIBF

We show the feasibility of determining the surface of matter density distributions of nuclei from experimental data of low yields by demonstrating how the fitted density distributions lose their shapes with the quality of data in the framework of χ2-fitting. We use various 'pseudo data' for the fitting, which simulate upcoming experiments at the RI-Beam Factory of RIKEN. In doing so, we propose a new Gaussian basis function for the expansion of the density distribution, which is found to be convenient for numerical calculations. Our procedure is equally applicable to both stable and unstable nuclei, though we have unstable nuclei in mind. (author)