The non-adiabatic dynamics of furan excited in the ππ* state (S2 Franck–Condon geometry) was studied using molecular simulations connection with an ensemble density functional method. time-resolved photoelectron spectra were theoretically simulated a wide range electron binding energies that covered valence as well core electrons. decay (rise) signal compared excited-state population dynamics. ...

We prove that CP violating rate difference ∆(B̄0 → π+π−) = Γ(B̄0 → π+π−)− Γ(B0 → π−π+) is related to ∆(B̄0 → π+K−) = Γ(B̄0 → π+K−)− Γ(B0 → π−K+) in the three generation Standard Model. Neglecting small annihilation diagrams, and in the SU(3) symmetry limit, we show ∆(B̄0 → π+π−) = −∆(B̄0 → π+K−). The SU(3) breaking effects are estimated using factorization approximation, and yield ∆(B̄0 → π+π−) ≈ −(fπ...

Scalar-isoscalar mesons are studied using an unitary model in three channels: ππ, KK and an effective 2π2π. All the solutions, fitted to the ππ and KK data, exhibit a wide f0(500), a narrow f0(980) and two relatively narrow resonances, lying on different sheets between 1300 MeV and 1500 MeV. These latter states are similar to the f0(1370) and f0(1500) seen in experiments at CERN. Branching rati...

Strong isospin-breaking (IB) effects in CP-even and CP-odd K → ππ decays are computed to next-to-leading order (NLO) in the chiral expansion. The impact of these corrections on the magnitude of the ∆I = 1/2 Rule and on the size of the IB correction, ΩIB, to the gluonic penguin contribution to ǫ /ǫ are discussed. In the presence of IB, the standard isospin decomposition of the K → ππ, K → ππ, ππ...

Roy’s equations are used to check if the scalar-isoscalar ππ scattering amplitudes fitted to experimental data fulfill crossing symmetry conditions. It is shown that the amplitudes describing the “down-flat” phase shift solution satisfy crossing symmetry below 1 GeV while the amplitudes fitted to the “up-flat” data do not. In this way the long standing ”up-down” ambiguity in the phenomenologica...

We report on a dispersion relation for the γγ → (ππ)I S-wave in isospin I emphasizing the low energy region. The f0(980) signal that emerges in γγ → ππ is also discussed. Our results could be used to distinguish between different ππ isoscalar S-wave parameterizations. We also calculate the width of the σ resonance to γγ and obtain the value Γ(σ → γγ) = (1.68±0.15) KeV. Finally, we elaborate on ...

Scalar-isoscalar mesons are studied using an unitary model in three channels: ππ, KK and an effective 2π2π. All the solutions, fitted to the ππ and KK data, exhibit a wide f0(500), a narrow f0(980) and two relatively narrow resonances, lying on different sheets between 1300 MeV and 1500 MeV. These latter states are similar to the f0(1370) and f0(1500) seen in experiments at CERN. Branching rati...

Complete next-to-leading (chiral) order (NLO) expressions for the strong isospin-breaking (IB) contributions in K → ππ are used to discuss (1) for CP-even, the impact on the magnitude of the ∆I = 1/2 Rule, and (2) for CP-odd, the strong IB correction, Ωst, for the gluonic penguin contribution to ǫ /ǫ, with particular emphasis on the strong low-energy constant (LEC) and loop contributions, numer...

The ππ interactions are one of the main sources of information on low energy physics. Their knowledge in scalar-isoscalar channel allows us to investigate scalar meson spectroscopy and to test the predictions of many theoretical models. Amplitudes of the ππ interactions should fulfill some basic conditions like unitarity and crossing symmetry. Described in 1) three-coupled channel amplitudes fo...