@techreport{oai:jaxa.repo.nii.ac.jp:00006108,
 author = {土山, 明 and 上杉, 健太朗 and 中野, 司 and Tsuchiyama, Akira and Uesugi, Kentaro and Nakano, Tsukasa},
 month = {Mar},
 note = {Densities of Hayabusa analog samples were measured without contamination using synchrotron X-ray microtomography at BL20XU of SPring-8 and an ultra-microbalance. The density of sample 2-1A is 6.37 +/- 0.02 g/cc. The density of sample 2-1B were scattered (5.05-7.18 g/cc). This may caused by volume estimation problem in the microtomography due to the presence of a large amount of highly absorbed materials (probably Fe-Ni metal) and less absorbed materials (probably silicates). Increment of the number of projection in the tomographic imaging will solve the problem. Three-dimensional grain size distribution of sample 2-1A was obtained by identification of individual grains in the 3-D CT (Computer-aided Tomography) images. This will give the basic physical properties of regolith, which may be present on Itokawa's surface. Several phases were recognized in the 3-D CT images using CT value histograms of the images, and their 3-D distribution maps were obtained with the spatial resolution of down to about 0.5 micrometer. This will helpful for planning later destructive analyses. The density, phase estimation (probably plagioclase, Fe-Mg silicates, troilite, kamacite and taenite in sample 2-1A and Fe-Mg silicates, kamacite and taenite in sample 2-1B if meteorites are assumed) and their modes and textures suggest possibility of an ordinary chondrite (LL (Low iron, Low metal) is favorable) with high petrologic type for sample 2-1A and a stony iron for sample 2-1B although the conclusion cannot be made definitely from the CT images alone. Subtraction microradiography was also applied to sample 2-1A to search Zr-bearing minerals effectively for the Pb-Pb dating. Any Zr-bearing minerals were not observed within the spatial resolution of about a few micrometer, but zircon grains added in sample 2-1A were easily recognized by this method., 資料番号: AA0063920004, レポート番号: JAXA-SP-05-021E},
 title = {Hayabusa analogue sample analysis using synchrotron imaging},
 year = {2006}
}