Pion and Sigma Polarizabilities and Radiative Transitions
نویسنده
چکیده
Fermilab E781 plans measurements of γ-Sigma and γ-pion interactions using a 600 GeV beam of Sigmas and pions, and a virtual photon target. Pion polarizabilities and radiative transitions will be measured in this experiment. The former can test a precise prediction of chiral symmetry; the latter for a1(1260)→ πγ is important for understanding the polarizability. The experiment also measures polarizabilities and radiative transitions for Sigma hyperons. The polarizabilities can test predictions of baryon chiral perturbation theory. The radiative transitions to the Σ∗(1385) provide a measure of the magnetic moment of the s-quark. Previous experimental and theoretical results for γπ and γΣ interactions are given. The E781 experiment is described.
منابع مشابه
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