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Volume 71 (2008)
- Issue 6 Pages 400-
- Issue 5 Pages 308-
- Issue 4 Pages 219-
- Issue 3 Pages 127-
- Issue 2 Pages 50-
- Issue 1 Pages 3-
Volume 71, Issue 4
Displaying 1-10 of 10 articles from this issue
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Kiyoshi NIU2008 Volume 71 Issue 4 Pages 219-228
Published: August 25, 2008
Released on J-STAGE: January 04, 2011
JOURNAL FREE ACCESSNaked charm particle, which contain singly the 4-th quark, charm or anti-charm, was discovered in 1971, in Japan, in a cosmic ray experiment using 2-fold emulsion trackers. It was 3 years in advance of discovery of hidden charm particle J/Ψ in United States, which consists of a pair of charm and anti-charm quarks. In 1975, we again discovered artificially produced naked charm particles produced by an accelerator at Fermilab. In the same year, we pointed out lifetime difference of a factor of 2-3 between charged and neutral components of charm particles produced by cosmic rays. A decade later, we reconfirmed this lifetime difference by an experiment in accelerator field using so called hybrid apparatus, which consists of 2-fold emulsion trackers and electronic detectors. Furthermore, we discovered 2 peculiar events, in which 2 pairs of charm particles (4 charm particles) in a same interaction, by another hybrid experiment at CERN. All of those results are remarkable ones in the history of charm physics.View full abstractDownload PDF (5663K) -
Toshiyuki NAKANO, Kunihiro MORISHIMA2008 Volume 71 Issue 4 Pages 229-233
Published: August 25, 2008
Released on J-STAGE: January 04, 2011
JOURNAL FREE ACCESSThe most important point of applying nuclear emulsion, which is true three-dimensional and one of the highest resolutions detector, to measurements of particle radiation is how to read and analyze quickly. We have developed an ultra high-speed nuclear emulsion readout system, the throughput of which is close to 100 cm2 an hour. The key points of this system are three-dimensional image acquisition and processing. The objective lens with piezo actuators allows reducing the repetition time of image acquisition and the newly developed processing board, which is based on FPGA technology, enables real time 3D image processing.View full abstractDownload PDF (9539K) -
Cristiano BOZZA2008 Volume 71 Issue 4 Pages 234-238
Published: August 25, 2008
Released on J-STAGE: January 04, 2011
JOURNAL FREE ACCESSThe European Scanning System is an automatic system for nuclear emulsions used in OPERA to read out emulsion plates. It is an evolution of the SySal system developed to scan nuclear emulsion plates in CHORUS. It integrates several commercial components to obtain a cheap, modular and efficient system that can evolve with technology. All processing steps are demanded to dedicated software, which implies a naturally flexible approach, easy to upgrade. While scanning emulsion images at the speed of 20cm2/h/side, 3D microtracks are reconstructed on-the-fly, with sub-micrometric precision. This is obtained through sophisticated image processing algorithms. Data are continuously sent from microscopes to computing machines in a cluster for higher-level processing such as smart scanning, decision-making to optimize scanning and on-line reconstruction. Information is immediately available in relational shape on an Oracle-based Database system, ready for sharing with other laboratories and analysis sites.View full abstractDownload PDF (6599K) -
Paolo STROLIN2008 Volume 71 Issue 4 Pages 239-244
Published: August 25, 2008
Released on J-STAGE: January 04, 2011
JOURNAL FREE ACCESSThe Kamiokande and Super-Kamiokande experiments, and independently the MACRO experiment, have observed a deficit, or “disappearance”, of muon neutrinos produced by cosmic rays which interact in the atmosphere. This effect is interpreted as the result of an “oscillation” of muon neutrinos into tau neutrinos. This interpretation must be confirmed by the direct observation of the “appearance” of tau neutrinos. The interaction of a tau neutrino with matter produces a short lived particle, the tau lepton, which can be taken as the signature of the phenomenon.
The discovery of the π meson and the first observation of a “charmed” particle, indicate that nuclear emulsions provide a powerful tool to detect short lived particles. The OPERA experiment make use of a massive Emulsion Cloud Chamber to search for the appearance of tau neutrinos in the CNGS beam from CERN to Gran Sasso, nominally consisting only of muon neutrino.
The OPERA experiment implies the application of the emulsion technique at a very large scale. It has required new developments for the industrial production of nuclear emulsions, for their treatment to induce a fading of background tracks and for automated emulsion scanning at very high speed. The experiment will start running for physics in 2008. An overview is given in this report.View full abstractDownload PDF (10852K) -
Kazuma NAKAZAWA2008 Volume 71 Issue 4 Pages 245-247
Published: August 25, 2008
Released on J-STAGE: January 04, 2011
JOURNAL FREE ACCESSWith use of 2.6t nuclear emulsion, we will perform the E07 (J-PARC) experiment which will provide about one hundred double hypernuclei. In the experiment, Xi hyperons are expected to be detected in the emulsion plate with Double-sided Silicon Strip Detectors, very fast and quite effectively. Ge detectors also work to present information of the strong interaction between a Xi hyperon and a nucleon by the measurement of X-ray, precisely, via Xi capture reaction. We start to optimize the development condition of wide and thick emulsion plates from now on.View full abstractDownload PDF (6189K) -
Toshiyuki TOSHITO2008 Volume 71 Issue 4 Pages 248-251
Published: August 25, 2008
Released on J-STAGE: January 04, 2011
JOURNAL FREE ACCESSWe have developed the method to detect fragmentation reactions of therapeutic carbon beams in tissue equivalent material such as water, and measured reaction cross sections. The results are useful to improve the dose calculation in the body of patients. We measure fragmentation reaction for various combinations of beams and target materials aiming to construct the reaction database for ion therapy.View full abstractDownload PDF (2887K) -
Giovanni De LELLIS2008 Volume 71 Issue 4 Pages 252-255
Published: August 25, 2008
Released on J-STAGE: January 04, 2011
JOURNAL FREE ACCESSIn the cancer treatment by the hadron-therapy, beams of Carbon nuclei present therapeutic advantages over proton beams. The knowledge of the fragmentation of Carbon nuclei when they interact with human tissues is important to evaluate the spatial profile of the energy deposition in the human body, hence maximizing the effectiveness in hitting the cancer with minimal damage to the neighbouring tissues. The measurement is also of interest for the evaluation of the biological damage by cosmic rays to astronauts in space missions.
Nuclear emulsions allow to measure particle trajectories with space resolution at the micrometric level. In the Emulsion Cloud Chamber (ECC) technique, nuclear emulsion films are interleaved with plates of passive material in a multiple sandwich structure. This allows to integrate the target and the fragment detector in a very compact structure. The development of techniques of controlled fading of particle tracks in nuclear emulsions has opened the way to measurements of the specific ionisation over a very broad dynamic range.
The data presented in this paper have been obtained by exposing an ECC to a beam of Carbon nuclei with 400 MeV/nucleon at the Heavy Ion Medical Accelerator in Chiba, Japan. The ECC consisted of emulsion films and, as passive material, of polycarbonate with a density similar to that of the human body.
We report on the identification of nuclear fragments through the measurement of their specific ionisation, linked to the electrical charge. The results provide also features of the interactions such as the scattering angles for the different ions. We finally report the measurement of the partial charge-changing cross-sections, and in particular the production cross-section of low charge fragments, which is poorly known. The cross-sections obtained in this work are compared to those available from other experiments.View full abstractDownload PDF (596K) -
Shigeki AOKI, Satoru TAKAHASHI, Emulsion Hybrid Gamma-ray Telescope G ...2008 Volume 71 Issue 4 Pages 256-258
Published: August 25, 2008
Released on J-STAGE: May 24, 2011
JOURNAL FREE ACCESSRevolutionary techniques have been developed to realize nuclear emulsion experiment for the long baseline neutrino oscillation study. Utilizing and optimizing these techniques on balloon borne cosmic-ray experiment, we are developing an emulsion hybrid gamma-ray telescope with good angular resolution unreached before.View full abstractDownload PDF (759K) -
II. Color-Forming Development, Part 2. The Realization of Coupler-Incorporated Materials and its Impact on the IndustryYasushi OISHI2008 Volume 71 Issue 4 Pages 259-275
Published: August 25, 2008
Released on J-STAGE: January 04, 2011
JOURNAL FREE ACCESSIn 1936 the dawn of the modern color photography was marked by the sudden introduction of Agfacolor Neu Reversal Film based on a revolutionary technology developed by W Schneider and his collaborators at Filmfabrik Wolfen, Agfa. The Agfa's technology enabled the materials to provide either negative or reversal images in a single color-developing step by incorporating the couplers in their emulsion layers. Competitively the researchers of Eastman Kodak Co. devised an alternative type of non-diffusible couplers, called “oil-protected”, having only a hydrophobic group in their molecule and they developed their product Kodacolor Aero Reveral Film in 1941. With the advent of the new subtractivecolor-photographic process, the various current additive ones declined quickly.View full abstractDownload PDF (3422K) -
A Detection Method of Metameric Color AreasKimiyoshi MIYATA, Hannu LAAMANEN, Timo JÄÄSKELÄINEN, Ma ...2008 Volume 71 Issue 4 Pages 276-286
Published: August 25, 2008
Released on J-STAGE: January 04, 2011
JOURNAL FREE ACCESSThe spectral reflectance of icons was measured by using a measurement system developed in our previous study, and the measured data were applied to detect metameric color areas in the icons. In this paper, a technique for detecting metameric color areas is proposed and examined by using a test chart and ten icons painted on wooden plates. In the proposed technique, a coefficient showing the degree of metamerism is proposed based on the point of view in color difference and spectral information. The experimental results can then be used to consider which parts of the icons have possibility of previous restoration treatments. Despite the necessity of further consideration using certain chemical analyses and so on to conclude whether or not the experimental results are reliable, they demonstrate that the proposed technique has the basicability to detect metameric color areas.View full abstractDownload PDF (18120K)
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