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  • 1
    Electronic Resource
    Electronic Resource
    Lepton flavor-changing scalar interactions and g-2 of the muon (2003)
    Springer
    The European physical journal 27 (2003), S. 577-585 
    Details
    ISSN: 1434-6052
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract. A systematic investigation on the muon's anomalous magnetic moment and a related lepton flavor-violating process such as $\mu\to e\gamma$ , $\tau\to e\gamma$ and $\tau\to \mu\gamma$ is made at the two-loop level in the models with flavor-changing scalar interactions. The two-loop diagrams with double scalar exchanges are studied and their contributions are found to be compatible with the ones from the Barr-Zee diagram. By comparing with the latest data, the allowed ranges for the relevant Yukawa couplings Yij in the lepton sector are obtained. The results show the hierarchical structure $Y_{\mu e, \tau e} \ll Y_{\mu \tau} \simeq Y_{\mu\mu}$ in the physical basis if $ \Delta a_{\mu}$ is found to be $〉50\times 10^{-11}$ . It deviates from the widely used ansatz in which the off-diagonal elements are proportional to the square root of the products of the related fermion masses. An alternative Yukawa coupling matrix in the lepton sector is suggested to understand the current data. With such a reasonable Yukawa coupling ansatz, the decay rate of $\tau\to \mu\gamma$ is found to be near the current experiment upper bound.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1140/epjc/s2003-01137-1
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  • 2
    Electronic Resource
    Electronic Resource
    CP asymmetry in $B \rightarrow \phi K_{S}$ in a general two-Higgs-doublet model with fourth-generation quarks (2004)
    Springer
    The European physical journal 36 (2004), S. 89-95 
    Details
    ISSN: 1434-6052
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract. We discuss the time-dependent CP asymmetry of the decay $B \rightarrow \phi K_{\mathrm {S}}$ in an extension of the standard model with both a two Higgs doublet and additional fourth-generation quarks. We show that, although the standard model with a two Higgs doublet and the standard model with fourth-generation quarks alone are not likely to largely change the effective $\sin 2 \beta$ from the decay $B \rightarrow \phi K_{\mathrm {S}}$ , the model with both an additional Higgs doublet and fourth-generation quarks can easily account for the possible large negative value of $\sin 2 \beta$ without conflicting with other experimental constraints. In this model, additional large CP violating effects may arise from the flavor-changing Yukawa interactions between neutral Higgs bosons and the heavy fourth-generation down type quark, which can modify the QCD penguin contributions. With the constraints obtained from $b \rightarrow s \bar{s} s$ processes such as $B \rightarrow X_{s} \gamma$ and $\Delta m_{B_{s}^{0}}$ , this model can lead to an effective $\sin 2 \beta$ as large as - 0.4 in the CP asymmetry of ${B \rightarrow \phi K_{\mathrm {S}}}$ .
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1140/epjc/s2004-01872-7
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  • 3
    Electronic Resource
    Electronic Resource
    Unified QCD determination of all vector meson coupling constants (1992)
    Springer
    The European physical journal 56 (1992), S. 443-446 
    Details
    ISSN: 1434-6052
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Coupling constants of all vector mesons are determined in QCD by means of a new QCD sum-rule method. The results are found to be sensitive to the binding energy (i.e. meson and quark mass differences). For standard values of quark masses we obtainf ϱ=202 MeV,f K*=216 MeV,f D*=212±22 MeV,f B*=138±42 MeV, $$f_{D_s^* } = 238 \pm 21\,MeV$$ and $$f_{B_s^* } = 163 \pm 45\,MeV$$ . Based on this approach the spin-flavour symmetry for the heavy quark systems are also discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01565953
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  • 4
    Electronic Resource
    Electronic Resource
    A detailed analysis ofD-,D s - andB-meson transition form factors and the determination of |V cb | (1990)
    Springer
    The European physical journal 48 (1990), S. 663-671 
    Details
    ISSN: 1434-6052
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract We study various transition form factors in semi-leptonic decays ofD-,D s -,B- andB s -mesons using the pole dominance assumption. The vector current form factor is found to have only a negligible contribution to the decay rates involving pseudoscalar to vector transitions. In view of this fact we evaluate the form factors from present experimental data on the exclusive semi-leptonic decay rateΓ and the ratioΓ l /Γ T of the longitudinal and transverse partial decay rates. Some non-leptonic two-body decay rates are also investigated using the factorization ansatz. Consistency with the semi-leptonic decays is found. The transition form factors of theD- andD s -mesons are found to contradict the predictions of quark model. In contrast, the experimental data on the transition form factors ofB-mesons are found to be consistent with the quark model predictions. The KM matrix element |V cb | is determined to be |V cb |=0.040±0.010, a value somewhat smaller than is usually chosen.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01614702
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  • 5
    Electronic Resource
    Electronic Resource
    Nearly degenerate mass and bimaximal mixing of neutrinos in the SO(3) gauge model of leptons (1999)
    Springer
    The European physical journal 10 (1999), S. 491-497 
    Details
    ISSN: 1434-6052
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract. A realistic scheme for masses and mixing of leptons is investigated in the model with gauged SO(3) lepton flavor symmetry. Within this scheme, a nearly bimaximal neutrino mixing pattern with a maximal CP-violating phase is found to be the only possible solution for reconciling both solar and atmospheric neutrino flux anomalies. Three Majorana neutrino masses are nearly degenerate and large enough to play a significant cosmological role. Lepton flavor-violating effects via SO(3) gauge interactions can be as large as the present experimental limits. Masses of the SO(3) gauge bosons are bounded to be above 24 TeV when the SO(3) gauge boson mixing angle $\theta_{F}$ and coupling constant $g'_{3}$ are taken to be the same as those ( $\theta_{W}$ and g) in the electroweak theory.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s100529900136
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  • 6
    Electronic Resource
    Electronic Resource
    T-odd andCP-odd triple momentum correlations in the exclusive semi-leptonic charm meson decayD→K *(Kπ)lv l (1992)
    Springer
    The European physical journal 55 (1992), S. 479-483 
    Details
    ISSN: 1434-6052
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract We studyT-odd andCP-odd triple momentum correlations in exclusive semi-leptonic charm meson decaysD→K *(Kπ)lv l . We define asymmetry ratios that measure the trueCP-violating effects, andT-odd triple momentum correlation effects from unitarity contributions. Possible newCP-violating contributions are parametrized in terms of an effective four-fermion Hamiltonian whereCP-violating effects should come from new non-standard sources. A detailed analysis of the left-right model and the Weinberg Higgs-boson model ofCP-violation is carried out.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01565109
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  • 7
    Electronic Resource
    Electronic Resource
    Lepton hadron angular correlations in semileptonic ∋ decays (1994)
    Springer
    The European physical journal 62 (1994), S. 413-419 
    Details
    ISSN: 1434-6052
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract We studyT-odd triple momentum correlations in exclusive semileptonic ∋-decays into three pseudoscalar mesons. We define asymmetry ratios that measure theseT-odd correlations and show how to separate the unitarity contribution from the trueCP-violating contributions. TheCP-violating contributions to the asymmetry ratios would have to come from new non-Standard Model sources as theCP-violating Standard Model contributions to the asymmetry ratios are zero. We discuss two extensions of the Standard Model that give rise to nonvanishingCP-violating triple momentum correlations, namely a left-right symmetric model and a multi Higgs boson model. Numerical results on triple momentum correlations are given for the three-pseudoscalar meson final statesK - π - π + andK - π - K +.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01555900
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  • 8
    Electronic Resource
    Electronic Resource
    Generalized on-shell renormalization of heavy quarks (1992)
    Springer
    The European physical journal 53 (1992), S. 325-329 
    Details
    ISSN: 1434-6052
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract A generalized on-shell (GOS) renormalization scheme of QCD is developed to evaluate the renormalization of heavy quark wave functions and currents. All large logarithms arising from the physical range of quark masses and momentum transferq 2 can be absorbed into wave function and vertex renormalization. Our results are more general than those of the heavy quark effective theory and agree with the latter only at zero recoil. The proposed GOS scheme is very suitable for the μ/m Q expansion. As an application we discuss the renormalization of the flavour changing currentsb-c, t-b andt-c.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01597572
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  • 9
    Electronic Resource
    Electronic Resource
    Unified QCD determination of all pseudoscalar leptonic decay constants (1992)
    Springer
    The European physical journal 54 (1992), S. 163-168 
    Details
    ISSN: 1434-6052
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Leptonic decay constants of all pseudoscalar mesons are determined in QCD by means of a new QCD sum-rule method. In the light meson and heavy quark limit the results are very similar and also agree with the well-known PCAC and scaling predictions respectively. The corrections to light meson pole dominance are generally small while those to the heavy quark limit are found to be sensitive to the binding energy (i.e. meson and quark mass differences). For standard values of quark masses we obtainf π=132 MeV,f k=161 MeV,f B=128±28 MeV,f D=175±13 MeV,f Bs=144±30 MeV andf Ds=193±12 MeV.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01881719
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  • 10
    Electronic Resource
    Electronic Resource
    Isolation, identification, and synthesis of sex pheromone components of female tea cluster caterpillar,Andraca bipunctata walker (Lepidoptera: Bombycidae) in Taiwan (1996)
    Springer
    Journal of chemical ecology 22 (1996), S. 271-285 
    Details
    ISSN: 1573-1561
    Keywords: Decapitated female moth ; octadecanal ; (E)-11-octadecenal ; (E)-14-octadecenal ; (E,E)-11,14-octadecadienal
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Octadecanal (18:Ald), (E)-11-octadecenal (E11–18:Ald), (E)-14-octadecenal (E14–18:Ald) and (E,E)-11,14-octadecadienal (E11,E14–18:Ald) were isolated and identified as major components from the pheromone glands of the tea cluster caterpillar,Andraca bipunctata, in Taiwan by analyzing the mass spectra of gland components and their DMDS adducts. GC retention times and mass spectra of the components were in agreement with those of authentic synthetic compounds. The average amount of 18:Ald,E11–18:Ald,E14–18:Ald andE11,E14–18:Ald per female gland (1 to 3 days old) was 121±76, 50±20, 187±75, and 237±110 ng, respectively, in a ratio of 20:8:31:41. SyntheticE11,E14–18:Ald caught more males than each of the other three components or blank control in field trapping tests.E11,E14–18:Ald is reported as an insect sex pheromone for the first time. Male antenna responded toE11,E14–18:Ald strongly in an EAG analysis. Furthermore, 4 hr after the injection of PBAN (pheromone biosynthetic activating neuropeptide) into decapitated female moths (2 days old), the percentage of theE11,E14–C18 Ald in the gland extract increased from 0% to 75.5%, which was also significantly more than that of unligated and uninjected control at 55.1%. All these data indicated thatE11,E14–18:Ald is the sex pheromone of theAndraca bipunctata in Taiwan.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02055098
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