Electromagnetic transition form factor and radiative corrections in decays of neutral pions

Radiative corrections to the decays

We calculate the rates and lepton (l) invariant mass distributions for decays of the form 0−+ → l+l−γ, which are important radiative corrections to the purely leptonic decays 0−+ → l+l−. Our approach uses the loop diagrams which arise by including the two photon intermediate state and we retain the imaginary parts of the loops a radiative extension of the ‘unitarity bound’ for the process. Thes...

RADIATIVE CORRECTIONS TO Kl2 DECAYS

We consider Kl2 decays to the order O(α). We perform a matching calculation, using a specific model with vector meson dominance in the long distance part and the parton model in the short distance part. By considering the dependence on the matching scale and on the hadronic parameters, and by comparing with the leading model independent predictions, we scrutinize the model dependence of the res...

3 Decays : Radiative Corrections and Ckm Unitarity

Electromagnetic Corrections for Pions and Kaons : Masses and Polarizabilities

The unknown constants in Chiral Perturbation Theory needed for an all orders analysis of the polarizabilities and electromagnetic corrections to the masses of the pseudo-Goldstone bosons are estimated at leading order in 1/Nc. We organize the calculation in an 1/Nc-expansion and separate longand short-distance physics contributions by introducing an Euclidean cut-off. The long-distance part is ...

Radiative corrections to top quark decays

These lectures held by one of us (JGK) at the II Helmholtz International Summer School on Heavy Quark Physics in Dubna, Russia (August 11 21 2008) are meant as pedagogical lectures aimed at the level of the audience which, on the participants’ side, was composed of graduate students with a few postdoctoral students mixed in. We give many details on the Born level calculation of rates and angula...