|Budget Amount *help
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 2002: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 2001: ¥3,100,000 (Direct Cost: ¥3,100,000)
The quality of nuclear emulsion is judged by the number of silver grains, which produced by minimum ionizing particles, per 100 μm, and the number of fogs per 1,000μm^3. Using a high magnification objective lens each grains are imaged in neighbor pixels of a CCD, assuming highest signals pixel position to be that of grains. Changing the focus depth a set of cross sectional images can be got. From those recorded data the number of grains per 100 μm of minimum ionizing tracks, which penetrated almost parallel to the plate. But if they are penetrated vertically to the plats it is rather difficult to discriminate each others, and so it is almost impossible to make quality check counting grain numbers.
Looking a set of images penetrated track is move linearly to the depth. The shift values per unit depth are dx/dz and dy/dz respectively. The super imposed image shifting some values shows a peak signal pixel with the existence of corresponding angle track. Picking up signals greater than some
threshold signal level tracks, Fully Automated Analyzing System were build at Nagoya University. In 2002 test beams of KEKPS were irradiated to ECC made by lead plates and Opera films, which produced by the collaboration with Fuji and Nagoya. The beam is set to plus charge and momentum to 1.2GeV/c. This beam is including protons and πmesons about fifty-fifty. The pulse height of tracks is measured in one plate, but the distribution is broad shape. In ECC a total of 29 films is consisted, and the mean value distribution of each tracks pulse height shows clear two peaks. Full automated Analyzing system was used for this analysis, but in principle it is possible to analyze with the machine made by this project. To detect grains of one or less micrometer size, it is essential to use a high magnification objective lens. And to get good quality images it is also essential to use good illumination system. The first target of this project is to make portable emulsion scanning system. It can be move by human power, but it is still heavy to move any places. It is necessary to build a compact and high quality illuminations. Less