294 research outputs found

    The β\beta angle as the CP violating phase in the CKM matrix

    Get PDF
    The CKM matrix describing quark mixing with three generations can be parameterized by three Euler mixing angles and one CP violating phase. In most of the parameterizations, the CP violating phase chosen is not a directly measurable quantity and is parametrization dependent. In this work, we propose to use the most accurately measured CP violating angle β\beta in the unitarity triangleas the phase in the CKM matrix, and construct an explicit β\beta parameterization. We also derive an approximate Wolfenstein-like expression for this parameterization.Comment: RevTex 7 pages with one figure. Version to be published in Phys. Lett. B. arXiv admin note: substantial text overlap with arXiv:1204.123

    The α\alpha, β\beta and γ\gamma parameterizations of CP violating CKM phase

    Full text link
    The CKM matrix describing quark mixing with three generations can be parameterized by three mixing angles and one CP violating phase. In most of the parameterizations, the CP violating phase chosen is not a directly measurable quantity and is parametrization dependent. In this work, we propose to use experimentally measurable CP violating quantities, α\alpha, β\beta or γ\gamma in the unitarity triangle as the phase in the CKM matrix, and construct explicit α\alpha, β\beta and γ\gamma parameterizations. Approximate Wolfenstein-like expressions are also suggested.Comment: 14 page, 1 figur

    Fabrication of Antireflection Nanodiamond Particle Film by the Spin Coating Deposition Technique

    Get PDF
    Diamond-based antireflective (AR) coatings were fabricated using a spin coating of diamond suspension at room temperature as nucleation enhancement procedure and microwave plasma enhanced chemical vapour deposition. Various working pressures were used to investigate their effect on the optical characterization of the as-deposited diamond films. Scanning electron microscopy (SEM) and atomic forced microscopy (AFM) were employed to analyze the surface properties of the diamond films. Raman spectra and transmission electron microscopy (TEM) also were used for analysis of the microstructure of the films. The results showed that working pressure had a significant effect on thickness, surface roughness, and wettability of the as-deposited diamond films. Deposited under 35 Torr or working pressure, the film possessed a low surface roughness of 13.8 nm and fine diamond grain sizes of 35 nm. Reflectance measurements of the films also were carried out using UV-Vis spectrometer and revealed a low reflectance value of the diamond films. The achievement demonstrated feasibility of the proposed spin-coating procedure for large scale production and thus opens up a prospect application of diamond film as an AR coating in industrial optoelectronic device
    • …
    corecore