Exchange Currents in Radiative Hyperon Decays and Hyperon Charge Radii
نویسنده
چکیده
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 experimental results from SELEX. Strangeness suppression is weakened by exchange currents for several observables.
منابع مشابه
Exchange Currents in Radiative Hyperon Decays
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تاریخ انتشار 1998