相关论文: Skyrme model and nonleptonic hyperon decays
The Skyrme model is reconsidered from an effective theory point of view. Starting with the most general Lagrangian up to including terms of order $p^4$, $N_c$ and $\delta m^2$ ($\delta m\equiv m_s-m$), we obtain new interactions, which have…
The analysis of hyperon semi-leptonic decay data is addressed with reference to SU(3) breaking and isospin mixing between Lambda^O and Sigma^O. Various approaches to SU(3) breaking are discussed and compared. The phenomenological…
Motivated by recent observations from Pamela, Fermi and H.E.S.S., we consider dark matter decays in the framework of supersymmetric SU(5) grand unification theories. An SU(5) singlet S is assumed to be the main component of dark matters,…
Hyperon nonleptonic decays that change strangeness by two units, such as $\Xi\to N\pi$ and $\Omega^-\to nK^-,\Lambda\pi^-,\Sigma^{(*)}\pi$, are highly suppressed in the standard model. Only a few of them have been searched for to date,…
We study the |Delta I|=3/2 amplitudes of hyperon non-leptonic decays of the form B->B'+pi in the context of chiral perturbation theory. The lowest-order predictions are determined in terms of only one unknown parameter and are consistent…
We give best covariant amplitude decompositions for two-body decay processes involving ground state hadrons ($0^-, 1^-, {1/2}^+, {3/2}^+$) and show how these are simply related to helicity amplitudes. After discussing how electromagnetic…
This lecture provides a pedagogical instruction to the basic concepts of the Skyrme model and its some applications. As the preliminary for understanding the Skyrme model, we first briefly explain the large $N_c$ expansion, chiral symmetry…
Purely baryonic weak decays of heavy baryons are investigated within the framework of the Skyrme model. These decays belong to a new class of unobserved decay channels, which would help us to test the standard model, particularly potential…
The Skyrme model is a low-energy effective field theory for QCD, where the baryons emerge as soliton solutions. It is, however, not so easy within the standard Skyrme model to reproduce the almost exact linear growth of the nuclear masses…
SU(3) breaking in hyperon semi-leptonic decays is discussed. The SU(3) parameters $F$ and $D$, relevant to the ``proton-spin puzzle'', are extracted and a prediction is presented for the decay Xi0 -> Sigma+ e anti-neutrino, currently under…
We present results for the semi-leptonic and leptonic decays of B mesons. These non-perturbative matrix elements are important for constraining the CKM matrix. Results are presented for the pseudoscalar and vector decay constants, as well…
Exclusive semileptonic and nonleptonic $J/\psi$ decays are investigated in the framework of the relativistic quark model based on the quasipotential approach and quantum chromodynamics. The form factors parameterizing the hadronic matrix…
In a finite volume, resonances and multi-hadron states are identified by discrete energy levels. When comparing the results of lattice QCD calculations to scattering experiments, it is important to have a way of associating the energy…
We study the density dependence of the decay $\pi^0\to \gamma \gamma$ using the Skyrme Lagrangian to describe simultaneously both the matter background and mesonic fluctuations. Pion properties such as mass and decay constant are modified…
We report a theoretical analysis of the exclusive non-leptonic decays of B mesons into two light mesons,some of which have been measured recently by the CLEO collaboration. Our analysis is carried out in the context of an effective…
In this talk I will discuss non-leptonic B decays, in particular how soft-collinear effective field theory (SCET) can be used to constrain the non-perturbative hadronic parameters required to describe the various observables.
In this talk I describe work on computing non-leptonic matrix elements consistently with both long and short distance contributions included. On the simpler example of the $\pi^+$-$\pi^0$ mass difference I explain in detail the matching…
The Skyrme model is reconsidered from an effective theory point of view. From the most general chiral Lagrangian up to including terms of order $p^4$, $N_c$ and $\delta m^2$ ($\delta m\equiv m_s-m$), new interactions, which have never been…
Long-distance effects in exclusive rare semileptonic transitions B -> (K, K*) are analysed within a relativistic quark model. The meson transition form factors, describing the meson amplitudes of the effective weak Hamiltonian, are…
We investigate the semileptonic and nonleptonic decays of $B_s$ mesons. We work within the context of nonrelativistic constituent quark models. We calculate the different form factors that parameterize the hadron matrix elements.