1999/02/22 by B. Borasoy, B. R. Holstein · 1 citation
Physics and Astronomy · #hep-ph
paper · pdf · doi:10.1103/physrevd.59.054019
published as Phys.Rev. D59 (1999) 054019 · 14 pages, 2 figures
arxiv created 1999/02/22 · arxiv updated 2009/11/30
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 parameter in polarized Sigma+ -> p gamma is found, in agreement with the experimental result alpha(p Sigma+) = -0.76 +/- 0.08.