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451.
A distinct peak is observed in the pi +/- psi' invariant mass distribution near 4.43 GeV in B-->K pi +/- psi' decays. A fit using a Breit-Wigner resonance shape yields a peak mass and width of M=4433+/-4(stat)+/-2(syst) MeV and Gamma=45-13+18(stat)-13+30(syst) MeV. The product branching fraction is determined to be B(B 0-->K -/+Z+/-(4430)) x B(Z+/-(4430)-->pi+/-psi')=(4.1+/-1.0(stat)+/-1.4(syst)) x 10(-5), where Z+/-(4430) is used to denote the observed structure. The statistical significance of the observed peak is 6.5 sigma. These results are obtained from a 605 fb(-1) data sample that contains 657 x 10(6) BB pairs collected near the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric energy e+ e- collider.  相似文献   
452.
We report the first measurement of CP-violation parameters in B0-->rho0gamma decays based on a data sample of 657x10(6)BB pairs collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. We obtain the time-dependent and direct CP-violating parameters, Srho0gamma=-0.83+/-0.65(stat)+/-0.18(syst) and Arho0gamma=-0.44+/-0.49(stat)+/-0.14(syst), respectively.  相似文献   
453.
We report a measurement of the CP-violating parameters in B;{0}-->K_{S}{0}K_{S}{0} decays based on a data sample of 657x10{6} BB[over ] pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e;{+}e{-} collider. In this Letter, one neutral B meson is fully reconstructed in the B;{0}-->K_{S}{0}K_{S}{0} decay mode, and the flavor of the accompanying B meson is identified by its decay products. The CP-violating parameters are measured from the asymmetry in the distributions of the proper-time interval between the two B decays: S_K_{S}{0}K_{S}{0}}=-0.38_{-0.77}{+0.69}(stat)+/-0.09(syst) and A_{K_{S}{0}K_{S}{0}}=-0.38+/-0.38(stat)+/-0.05(syst).  相似文献   
454.
The need for the comparative analysis of terrestrial soil-mineral systems and Martian rocks is shown for the first time by examples from concrete research results using Mössbauer spectroscopy. The proposed technique is effective in considering and studying the processes that occur in multicomponent natural objects. A method for dividing magnetic particles into cosmic and technogenic is advanced as a hypothesis.  相似文献   
455.
The experimental results on breakdown characteristics of a discharge gap containing water vapor are presented. The results obtained show that the breakdown voltage between metal electrodes placed above water and when one electrode is immersed in water significantly increases at a saturated vapor temperature of 90°C and above. This effect can be an explanation of the features of the electric discharge development above the water surface.  相似文献   
456.
The rare decay K L 0 → π0ν $ \tilde v $ branching ratio measurement is one of the clearest Standard Model test. Calculations based on the SM predict Br(K L 0 → π0ν $ \tilde v $ ) ≈ 2.8 × 10?11, but the most accurate experimental value Br(K L 0 → π0ν $ \tilde v $ ) < 6.7 × 10?8 (90% C.L.). We present design of a new experimental setup KLOD (U-70 accelerator, IHEP, Protvino) for K L 0 → π0ν $ \tilde v $ branching ratio measurement. Sensitivity of the KLOD experiment will be enough for registration of 2.4 events K L 0 → π0ν $ \tilde v $ for every 10 days of the data taking (according to SM predictions).  相似文献   
457.
Distinct cellular domains, such as structure–function compartments of the cell nucleus and cytoplasmic organelles, are responsible for numerous macromolecular processes essential for cell functions. Spectroscopic analysis of specific cellular domains opens a way for noninvasive characterization of their molecular content and monitoring of their function. Confocal Raman spectroscopy was employed here for characterization of the complex molecular organization of major structure–function compartment of the cell nucleus, the nucleolus. The Raman spectra obtained in the nucleoli were processed by biomolecular component analysis (BCA). BCA was used to determine the contribution of each major type of macromolecules (proteins, DNA, RNA and lipids) to the complex molecular composition of nucleoli. A notable cell‐to‐cell variability in the macromolecular composition of nucleolus was found. At the same time, we observed a correlation between the concentrations of major types of biomolecules in this nuclear compartment. In particular, the averaged concentration of RNA increases along with increase in protein concentration, while an inverse dependence between the concentrations of RNA and DNA was found. Variations in the nucleolar concentrations of lipids were also noticed. Manifestations in spectral variations of proteins for individual nucleoli, shown by BCA, are discussed and interpreted. We also compared utility of BCA and principal component analysis for biomolecular studies and conclude that BCA is a more powerful and informative technique for studies of macromolecular composition and its variations in specific subcellular domains. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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