Decay widths and energy shifts of ππ and πK atoms

ar X iv : h ep - p h / 04 05 03 4 v 1 5 M ay 2 00 4 Spectra and decays of ππ and πK atoms

We describe the spectra and decays of π + π − and π ± K ∓ atoms within a non-relativistic effective field theory. The evaluations of the energy shifts and widths are performed at next-to-leading order in isospin symmetry breaking. We provide general formulae for all S-states, and discuss the states with angular momentum one in some detail. The prediction for the lifetime of the π ± K ∓ atom in ...

2 00 2 Dispersion relations and Omnès representations for K → ππ decay amplitudes

We derive dispersion relations for K → ππ decay, using the Lehmann-Symanzik-Zimmermann formalism, which allows the analytic continuation of the amplitudes with respect to the momenta of the external particles. No off-shell extrapolation of the field operators is assumed. We obtain generalized Omnès representations, which incorporate the ππ and πK S-wave phase shifts in the elastic region of the...

Dispersion relations and Omnès representations for K decay amplitudes

We derive dispersion relations for K → ππ decay, using the LehmannSymanzik-Zimmermann formalism, which allows the analytic continuation of the amplitudes with respect to the momenta of the external particles. No off-shell extrapolation of the field operators is assumed. We obtain generalized Omnès representations, which incorporate the ππ and πK S-wave phase shifts in the elastic region of the ...

Investigation of ππ and πK atoms at DIRAC

Constraining Penguin Contributions and the CKM Angle γ through B d → π + π −

The decays Bd → ππ and Bs → KK provide an interesting strategy to extract the CKM angle γ at “second-generation” B-physics experiments of the LHC era. A variant for “first-generation” experiments can be obtained, if Bs → KK is replaced by Bd → πK. We show that the most recent experimental results for the CP-averaged Bd → ππ and Bd → πK branching ratios imply a rather restricted range for the co...