13 research outputs found

    On the Origin of the Enhancementof CP-violating Charge Asymmetries in K3πK \rightarrow 3\pi Decays Predicted from Chiral Theory

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    We present an analysis of the enhancement of CP-violating charge asymmetries in K3πK \rightarrow 3\pi decays. Calculations of decay amplitudes are performed on the basis of bosonized strong and weak Lagrangians derived from QCD-motivated quark Lagrangians. We show that the interplay of fourth-order contributions of chiral Lagrangians for strong interactions and penguin operators in weak interactions significantly enhances the charge asymmetries.Comment: DESY 92-106, 15

    Calculation of Heat-Kernel Coefficients and Usage of Computer Algebra

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    The calculation of heat-kernel coefficients with the classical DeWitt algorithm has been discussed. We present the explicit form of the coefficients up to h5h_5 in the general case and up to h7minh_7^{min} for the minimal parts. The results are compared with the expressions in other papers. A method to optimize the usage of memory for working with large expressions on universal computer algebra systems has been proposed.Comment: 12 pages, LaTeX, no figures. Extended version of contribution to AIHENP'95, Pisa, April 3-8, 199

    Vector and Scalar Meson Resonances in KπππK\rightarrow\pi\pi\pi Decays

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    Corrections to KπππK\rightarrow\pi\pi\pi induced by vector and scalar meson exchange are investigated within chiral perturbation theory.Comment: 15pages, Latex-file, TUM-T31-41/9

    Quadrupole polarizabilities of the pion in the Nambu--Jona-Lasinio model

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    The electromagnetic dipole and quadrupole polarizabilities of the neutral and charged pions are calculated in the Nambu--Jona-Lasinio model. Our results agree with the recent experimental analysis of these quantities based on Dispersion Sum Rules. Comparison is made with the results from the Chiral Perturbation Theory.Comment: 9 pages, 1 fi

    Charged Kaon K \to 3 pi CP Violating Asymmetries at NLO in CHPT

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    We give the first full next-to-leading order analytical results in Chiral Perturbation Theory for the charged Kaon K \to 3 pi slope g and decay rates CP-violating asymmetries. We have included the dominant Final State Interactions at NLO analytically and discussed the importance of the unknown counterterms. We find that the uncertainty due to them is reasonable just for \Delta g_C, i.e. the asymmetry in the K^+ \to pi^+ pi^+ pi^- slope g; we get \Delta g_C = -(2.4 +- 1.2) 10^{-5}. The rest of the asymmetries are very sensitive to the unknown counterterms. In particular, the decay rate asymmetries can change even sign. One can use this large sentivity to get valuable information on those counterterms and on Im(G_8) coupling --very important for the CP-violating parameter epsilon'_K-- from the eventual measurement of these asymmetries. We also provide the one-loop O(e^2 p^2) electroweak octet contributions for the neutral and charged Kaon K \to 3 pi decays.Comment: 43+2 pages, 2 figures. Version accepted in JHEP. Small changes in the final numerics of CP asymmetries due to change in input valu
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