http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Search for strange tribaryons in the He4(K<i>stop</i>−,n<sup>π±</sup>) reaction
Yim, H.,Bhang, H.,Chiba, J.,Choi, Seonho,Fukuda, Y.,Hanaki, T.,Hayano, R.S.,Iio, M.,Ishikawa, T.,Ishimoto, S.,Ishiwatari, T.,Itahashi, K.,Iwai, M.,Iwasaki, M.,Kienle, P.,Kim, J.H.,Matsuda, Y.,Ohnishi, Elsevier 2010 Physics letters: B Vol.688 No.1
<P><B>Abstract</B></P><P>We have recently reported on an indication of the strange tribaryon state, S<SUP>+</SUP>, with a mass M∼3140 MeV/<SUP>c2</SUP> and width Γ<23 MeV/<SUP>c2</SUP>, in the neutron time-of-flight (TOF) spectrum of the He4(K<I>stop</I>−,n<SUP>π±</SUP>) reaction of the KEK-PS E471 experiment in a search for the deeply bound narrow <SUP>K−</SUP>ppn (total isospin T=0) state. In an attempt to confirm the state and search for other possible T=0, 1 tribaryonic states, we have re-measured the neutron energy spectrum of the same reaction in the KEK-PS E549 experiment with an upgraded setup for which the TOF resolution was improved 1.5 times and the statistics was increased 6 times. However, in the neutron spectra, we find such a smooth distribution that we conclude the state is either not so strong to stick out of the inclusive background or too broad to be identified as a distinct peak. We estimated the upper limits of the formation probability of the possible tribaryonic state for three widths, 0, 20, and 40 MeV/<SUP>c2</SUP>. The obtained upper limit (95% CL) for a state as narrow as 20 MeV/<SUP>c2</SUP> is at most 1% per stopped kaon over the wide mass range of 3000–3200 MeV/<I>c</I><SUP>2</SUP>, while it reaches to 4∼5% at around 3140 MeV/<I>c</I><SUP>2</SUP> for Γ⩾40 MeV/<SUP>c2</SUP>, implying the possible existence of unknown processes including tribaryonic formation.</P>
S. Ohnishi,K. Kondo,S. Sato,K. Ochiai,K. Takakura,C. Konno,I. Murata 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.23
A new collimator system was constructed to produce a new collimated DT neutron beam for new integral benchmark experiments at the first target room of the Fusion Neutronics Source facility in Japan Atomic Energy Agency. The collimator system had been designed and optimized with a neutron transport calculation code and the performance of the collimated DT neutron beam was tested with an imaging plate, activation foil and a scintillation counter. The DT neutron flux at the exit of the collimator hole was 2.22 × 10^6 cm^(-2)s^(-1), which was 239 times as large as that at the 2 cm off-centered position. It was confirmed that the new DT neutron beam had a good performance as expected.
Insufficient Self-Shielding Correctionin JSSTDL-300
C. Konno,K. Ochiai,S. Ohnishi 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.23
JSSTDL-300 is a multigroup library for shielding applications produced from JENDL-3.2. The self-shielding correction in JSSTDL-300 is probably inadequate due to the following two reasons, 1) the weighting flux of Legendre order 0 is applied to all Legendre orders, 2) the f-table of the scattering matrix is the same as that of the elastic scattering. Thus we examined the effects of these problems through a simple benchmark test, the model of which consisted of an aluminum, iron, nickel or copper sphere of 1 m in radius with a 20 MeV neutron source in the center. Neutron spectra in the sphere were calculated with ANISN and they were compared with those obtained with MCNP4C. It was found out that the effects were dependent on materials and were the largest for copper. Adequate f-table data and weighting flux should be adopted in generation of multigroup libraries.
Katsumi Kobayashi,K. Sadasivan Pillai,Mathews Michael,K.M. Cherian,Mariko Ohnishi 한국실험동물학회 2010 Laboratory Animal Research Vol.26 No.2
In repeated-dose 28-day oral toxicity study design, the low dose is fixed as the no observed effect level (NOEL). But, in practice the low dose usually shows significant difference in few measurable items in most of the studies. We investigated 109 of repeated-dose 28-day oral toxicity studies in rats conducted according to the Chemical Substance Control Law, Japan and examined the measurable items (functional observational battery, urinalysis, hematology, blood chemistry and absolute and relative organ weights) of the low dose group which showed a statistical significant difference (P<0.05) compared to the respective control groups. The investigation revealed that, 205/12,167 (1.6%) measurable items showed a significant difference in the low dose groups. The significant difference shown by urinalysis was high (3.3%), followed by clinical chemistry parameters, hematology, relative organ weights and absolute organ weights (1.8-1.1%). We conclude from the investigation that the low dose may be considered as NOEL, if the significant difference of measurable items of it is about 2% (maximum <5%), compared to the control. However, due consideration may be given to the clinical relevance of the items that showed a significant difference.
Usui, T.,Urano, K.,Suzuki, S.,Hioki, K.,Maruyama, Ch.,Tomisawa, M.,Ohnishi, Y.,Suemizu, H.,Yamamoto, S. Korean Society of ToxicologyKorea Environmental Mu 2001 Toxicological Research Vol.17 No.-
The international pharmaceutical and regulatory communities had been recognizing the limited utility of conventional rodent carcinogenicity study particularly on the second species, mouse, after intense investigation of carcinogenicity data base worldwide, and a new scheme for carcinogenicity testing for pharmaceuticals was proposed at the Expert Working Group on Safety in the International Conference on Harmonization (ICH) in 1996. CB6F 1-Tg rasH2 mouse carrying human prototype c-Ha-ras gene with its own promoter/enhancer is one oj the new carcinogenicity assay model for human cancer risk assessment. Studies have been conducted since 1992 to validate the transgenic (Tg) mice for rapid carcinogenicity test-ing, short term (26 weeks) studies with genotoxic (by Salmonella), non-genotoxic carcinogens, genotoxic non-carcinogens, non-genotoxic non-carcinogens revealed relatively high concordance oj the response of the Tg mouse with classical bioassay across classes of carcinogenic agents. Mechanistic basis for carcinogensis in the model are being elucidated in terms of the role of overexpression and/or point mutation of the transgene. This report review the initial studies of validation of the model and preliminary results of on-going ILSI HESI ACT project will be presented.