118783546
Masslessness of the up quark and eta-->3pi0 decay
15057916
Non-Hermitian Hamiltonians with real and complex eigenvalues in a Lie-algebraic framework
Abstract We show that complex Lie algebras (in particular sl (2, C ) ) provide us with an elegant method for studying the transition from real to complex eigenvalues of a class of non-Hermitian Hamiltonians: complexified Scarf II, generalized Poschl–Teller, and Morse. The characterizations of these Hamiltonians under the so-called pseudo-Hermiticity are also discussed.
14482980
Lattice Bosons
Fermions on the lattice have bosonic excitations generated from the underlying periodic background. These , the lattice bosons , arise near the empty band or when
121162336
Radiative decays of vector mesons and off-shell factors in the vector-dominance model
The recent measurements of V ..-->.. P..gamma.. decays have led to a number of theoretical formulations to explain the low rates. In the vector-meson-dominance model this is accomplished by introducing a suppression factor at one of the vertices of the off-shell vector meson, but this leads to inconsistencies when compared with experimental data. For the case of new mesons we have found that suppression factors need to be introduced at both vertices to give a good fit to the data. In this paper we show that this scheme, applied to the case of the old mesons assuming only simple SU(3), gives fits that are as good as or better than other generally more complicated models.
119341722
Nonet symmetry, anomalous Ward identities and meson-gluonium mixing
TheSU(3) flavour structure of ι(1460) is exploited to seek consistency between vector meson dominance and anomalous Ward identities. Our analysis shows that a minimum of 10 to 20% breaking in nonet symmetry is necessary to get an overall fit with the radiative rates of low-lying η and η′.
36046285
Flavor violation in Higgs-boson couplings to baryons.
The 1/2{sup +} baryon mass spectrum is studied to determine the {ital {bar u}u}, {ital {bar d}d}, and {ital {bar s}s} contents in the nucleon. We find that higher-order symmetry-breaking terms in the mass operator are necessary to estimate {l angle}{ital p}{vert bar}{ital {bar u}u}{vert bar}{ital p}{r angle}, {l angle}{ital p}{vert bar}{ital {bar d}d}{vert bar}{ital p}{r angle}, and {l angle}{ital p}{vert bar}{ital {bar s}s}{vert bar}{ital p}{r angle} in a self-consistent way. We also assess the scalar (pseudoscalar) Higgs-boson couplings to baryons.
122098164
Analytic solutions in configuration space representation for scattering from a class of separable nonlocal potentials
122334428
Integral equations and the bound‐state problem
An integral equation for the s‐wave bound‐state solution is derived and then solved for a square‐well potential. It is shown that the scattering solutions continue to exist at negative energies, and when evaluated at the energy of a bound state these solutions do reduce to the bound‐state solution. The bound‐state energies of a square‐well potential are deduced also from orthogonality considerations. Finally, the existence of bound states for an arbitrary short‐range potential is related to the occurrence of zeros of the Jost function or poles of the S matrix for that potential.