64,035 research outputs found

    CP violation and final state interactions in B --> K pi pi decays

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    Effects of CP violation and of final state interactions between pairs of pseudoscalar mesons are studied in three-body B+, B-, B0 and antiB0 decays into K pi pi. An alternative approach to the isobar model for three-body B decays is proposed. It is based on the QCD factorization approximation and the knowledge of the meson-meson form factors. Some phenomenological charming penguin amplitudes are needed to describe the branching fractions, direct CP asymmetries of the quasi-two-body B --> K*(892) pi and B --> K0*(1430) pi decays as well as the K pi effective mass and the helicity angle distributions. The experimental branching fractions for the B --> K0*(1430) pi decay, obtained by the Belle and BaBar collaborations using the isobar model, are larger than our predictions by about 52 per cent.Comment: 3 pages, contribution to International Europhysics Conference on High Energy Physics HEP 2007, Manchester (England), July 19-25, 200

    Implications of Recent Bˉ0→D(∗)0X0\bar{B}^0\to D^{(*)0}X^0 Measurements

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    The recent measurements of the color-suppressed modes Bˉ0→D(∗)0π0\bar B^0\to D^{(*)0}\pi^0 imply non-vanishing relative final-state interaction (FSI) phases among various Bˉ→Dπ\bar B\to D\pi decay amplitudes. Depending on whether or not FSIs are implemented in the topological quark-diagram amplitudes, two solutions for the parameters a1a_1 and a2a_2 are extracted from data using various form-factor models. It is found that a2a_2 is not universal: ∣a2(Dπ)∣=0.40−0.55|a_2(D\pi)|= 0.40-0.55 and ∣a2(D∗π)∣=0.25−0.35|a_2(D^*\pi)|= 0.25-0.35 with a relative phase of order (50−55)∘(50-55)^\circ between a1a_1 and a2a_2. If FSIs are not included in quark-diagram amplitudes from the outset, a2eff/a1effa_2^{eff}/a_1^{eff} and a2effa_2^{eff} will become smaller. The large value of ∣a2(Dπ)∣|a_2(D\pi)| compared to ∣a2eff(Dπ)∣|a_2^{eff}(D\pi)| or naive expectation implies the importance of long-distance FSI contributions to color-suppressed internal WW-emission via final-state rescatterings of the color-allowed tree amplitude.Comment: 17 pages. The Introduction is substantially revised and the order of the presentation in Sec. 2 is rearranged. To appear in Phys. Re

    Inclusive Decays of Bottom Hadrons in New Formulation of Heavy Quark Effective Field Theory

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    We apply the new formulation of heavy quark effective field theory (HQEFT) to the inclusive decays of bottom hadrons. The long-term ambiguity of using heavy quark mass or heavy hadron mass for inclusive decays is clarified within the framework of the new formulation of HQEFT. The 1/mb1/m_b order corrections are absent and contributions from 1/mb21/m_b^2 terms are calculated in detail. This enables us to reliably extract the important CKM matrix element ∣Vcb∣|V_{cb}| from the inclusive semileptonic decay rates. The resulting lifetime ratios τ(Bs0)/τ(B0)\tau(B^0_s)/\tau(B^0) and τ(Λb)/τ(B0)\tau(\Lambda_b)/\tau(B^0) are found to well agree with the experimental data. We also calculate in detail the inclusive semileptonic branching ratios and the ratios of the τ\tau and β\beta decay rates as well as the charm countings in the B0B^0, Bs0B^0_s and Λb\Lambda_b systems. For B0B^0 decays, all the observables are found to be consistent with the experimental data. More precise data for the B0B^0 decays and further experimental measurements for the Bs0B^0_s and Λb\Lambda_b systems will be very useful for testing the framework of new formulation of HQEFT at the level of higher order corrections.Comment: 20 pages, RevTex, 8 figures, 3 tables, revised version with `dressed heavy quark' being addressed, to be published in Int. J. Mod. Phys.

    Entrepreneurial Inclination Among Business Students: a Malaysian Study

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    Entrepreneurship has been the fundamental topics of discussion among the politicians, economists, and academics. Business creation is especially critical in developing countries to stimulate economic growth. The present study attempts to examine entrepreneurial inclination among students who are a potential source of entrepreneurs. The fi ndings of the present research study indicate that majority of our business students are not entrepreneurial-inclined. They do not seem to possess strong entrepreneurial characteristics and entrepreneurial skills, and they are not keen in starting a new business. The roles of higher institutes of education and the government in promoting entrepreneurship are discussed

    k-String tensions and the 1/N expansion

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    We address the question of whether the large-N expansion in pure SU(N) gauge theories requires that k-string tensions must have a power series expansion in 1/N^2, as in the sine law, or whether 1/N contributions are also allowable, as in Casimir scaling. We find that k-string tensions may, in fact, have 1/N corrections, and consistency with the large-N expansion in the open-string sector depends crucially on an exact cancellation, which we will prove, among terms involving odd powers of 1/N in particular combinations of Wilson loops. It is shown how these cancellations are fulfilled, and consistency with the large-N expansion achieved, in a concrete example, namely, strong-coupling lattice gauge theory with the heat-kernel action. This is a model which has both a 1/N^2 expansion and Casimir scaling of the k-string tensions. Analysis of the closed string channel in this model confirms our conclusions, and provides further insights into the large-N dependence of energy eigenstates and eigenvalues.Comment: RevTeX4, 21 pages. Typos corrected, references added, some discussions expanded; conclusions unchanged. Version to appear on PR
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