Elemental mapping and estimation of elemental abundances of lichen by TIARA micro beam PIXE

Iwata, Yoshihiro*; Ishii, Keizo*; Kamiya, Tomihiro; Sato, Takahiro

Distribution and abundance of several elements in a lichen sample were searched by micro beam PIXE. Dried fruticose linen (Cladonia amaurocraea (Florke) Schaer.) was cut to 25 m slice sample and mounted on the target folder. It was subjected to 3 MeV proton bombardments by the micro beam PIXE system of TIARA. The elemental maps made by the distribution of K and Cl show the shape of the section of the lichen slice. S and P were mainly distributed on the upper cortical layer. Si deposited between inner cortical layer and algal layer, and also deposited on the inner wall of algal layer. Elemental abundances for S, P and Ca were estimated by the intensity of characteristic X-ray and analytical sensitivity of the micro beam PIXE, for instance, S in the upper cortical layer was 2.6 mg cm and Ca in the algal layer was 0.2 mg cm.