To make the ππ state with non-zero relative momentum as the leading exponential, we impose anti-periodic boundary condition on the pion, which is implemented by imposing G-parity or H-parity on the quark fields at the boundary. With this, we calculate the I = 2 ππ phase shift from lattice simulation by using Lüscher's formula.

Thermal Bergman cyclization of Pt(II) dialkynylporphyrins reveals a marked reduction in the cyclization temperature relative to the free base and Zn(II) derivatives. In contrast, photogenerated (3)ππ* population produces no detectable Bergman photocyclization, suggesting that the photoreactivities of the related free base and Zn(II) derivatives occurs via the (1)ππ* state.

The scalar-isoscalar, scalar-isotensor and vector-isovector ππ amplitudes have been fitted simultaneously to experimental data and to to Roy’s equations. Resulting ππ phase shifts up to 1600 MeV and near threshold observables have been analyzed. Only the amplitudes fitted to the ”down-flat” set of phase shifts in scalarisoscalar wave fulfill crossing symmetry conditions and can be regarded as p...

We review our recent work on unitarization and chiral perturbation theory both in the ππ and the πN sectors. We pay particular attention to the Bethe-Salpeter and Inverse Amplitude unitarization methods and their recent applications to ππ and πN scattering.

Paramagnetic metals are frequently used to regulate fluorescence emissions in chemical and biological probes. Accurate quantum calculations offer the first regulation theory that quenching is through the competitive nonradiative decay of the mixed fluorophore/metal (3)ππ*/dd state isoenergetic to the fluorophore-localized (1)ππ* state.

The leading twist parametrization of dipion mass distribution in hard exclusive reactions is proposed. Its parameters are related to quark distributions (usual and skewed) in the pion and to distributions amplitudes of mesons (π, ρ, etc.). We show that measurements of the shape of dipion mass distribution in hard exclusie reactions can give important information about partonic structure of the ...

We evaluate radiative decays of ρ and ω going to two neutral mesons, ππ and πη. We use the sequential vector decay mechanisms in addition to chiral loops and ρ-ω mixing. The chiral loops are obtained using elements of UχPT successfully applied in the study of meson-meson interactions up to 1.2 GeV. The chiral loops are found very important in the case of the ρ → ππγ decay and small in the other...

We review recent advances in the theory of strong-interaction effects and final-state interactions in hadronic weak decays of heavy mesons. In the heavy-quark limit, the amplitudes for most nonleptonic, two-body B decays can be calculated from first principles and expressed in terms of semileptonic form factors and lightcone distribution amplitudes. We summarize the main features of this novel ...

We evaluate radiative decays of ρ and ω going to two neutral mesons, ππ and πη. We use the sequential vector decay mechanisms in addition to chiral loops and ρ-ω mixing. The chiral loops are obtained using elements of UχPT successfully applied in the study of meson-meson interactions up to 1.2 GeV. The chiral loops are found very important in the case of the ρ → ππγ decay and small in the other...

We study ǫ/ǫ in the Standard Model and ǫ/ǫ due to anomalous WWγ and WWZ interactions as a function of the top quark mass. In the Standard Model, ǫ/ǫ is in the range 10−3 ∼ 10−4 for the central value of top quark mass reported by CDF. The anomalous gauge couplings can have large contributions to the CP violating I = 2 amplitude in K → ππ. Within the allowed regions for the anomalous gauge coupli...