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Specific surface free energy (SSFE) of natural calcium fluorapatite from the same mother rock and synthesized barium chlorapatite from the same lot was determined using contact angle of water and formamide droplets, compared with grown length of crystal face (h). The experimentally obtained SSFEs have different values even for the same index faces of the different crystals. The SSFEs also have wide distribution for each face of crystals. Observed SSFE is considered to be not only the SSFE of ideally flat terrace face, but also includes the contribution of strep free energy. Though the crystals we experimentally obtained were growth form, the relationship between SSFE and h was almost proportional, which looks like satisfying Wulff's relationship qualitatively. The slope of SSFE versus h line shows the driving force of crystal growth, and the line for larger crystal has less steep slope. The driving force of crystal growth for larger crystal is smaller, which also means that the chemical potential is larger for larger crystal. The individuality of crystals for the same lot can be explained by the difference of the chemical potential of each crystal.

This study shows the variation of the characteristics of a plasma bullet generated in impurity controlled working gas. Tunable diode laser absorption spectroscopy of metastable He atoms generated in the plasma bullet was performed. The metastable He atoms are generated in the plasma bullet and are quenched by impurities. The velocity and the size of the plasma bullet are derived from the arriving time and the shape of the rising phase of the absorbance. In addition, the impurity concentration was derived from the decay time of the absorbance. The impurity concentration in the working gas is controlled in a range of more than two orders of magnitude, and the impurity concentration reaches ppb level. We have observed the impurity dependence of the velocity and size of the plasma bullet. The velocity of the plasma bullet reaches a constant value and the bullet size dramatically increase below 20 ppm of the impurities. These results show the change of the propagation mechanism of the plasma bullet in the high purity working gas. In order to distinguish the plasma generated in the high purity gas from the standard plasmas, we would call it ultrapure plasma.

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An experiment to measure the Z+p scattering cross sections was carried out at KEK 12 GeV proton synchrotron. A scintillating fiber active target system was used as a hydrogen target for the hyperon production and subsequent hyperon-nucleon scattering. Out of 1.3 x 10 6 hyperon production events, 31 events were identified as 2 + p elastic scattering events in the momentum region of 350 < p%+ < 750 MeV/c. Differential cross sections in the angular region of -0.8 < cos QCM < 0.8 and integrated cross sections with respect to the incident momentum were obtained. They were compared with the theoretical calculations.