Hyperon radiative decay

Hyperon radiative decay.

Strangeness Dependence in Radiative Hyperon Decay Amplitudes

The radiative decays of the 3 2 + baryons are studied in the three flavor generalization of the Skyrme model. The kaon fields are treated in the slow rotator approach which properly accounts for the observed deviations from the U–spin relations for the hyperon magnetic moments. This makes possible a critical discussion of the U–spin selection rules for the radiative hyperon decays. The variatio...

Weak Radiative Hyperon Decays

It is shown that an alternative form of the parity-nonconserving (PNC) transition electromagnetic current resolves partly a puzzle with the Hara theorem. New formulation of it has allowed PNC weak radiative hyperon transitions of the charged hyperons Σ+ ⇒ p + γ and Ξ ⇒ Σ + γ revealing hitherto unseen transition toroid dipole moment.

Resonances in radiative hyperon decays

The importance of resonances for the radiative hyperon decays is examined in the framework of chiral perturbation theory. Low lying baryon resonances are included into the effective theory and tree contributions to these decays are calculated. We find significant contributions to both the parity-conserving and parity-violating decay amplitudes and a large negative value for the asymmetry parame...

Exchange Currents in Radiative Hyperon Decays and Hyperon Charge Radii

Radiative decays of decuplet hyperons and octet hyperon charge radii are evaluated in a chiral constituent quark model emphasizing the role of exchange currents. Exchange currents largely cancel for the M1 decay amplitudes, while they dominate the E2 amplitude. Due to the pseudoscalar meson cloud the charge radii of Σ and Ξ are almost as large as the proton radius, in agreement with recent expe...