Low – energy photon – photon fusion into three pions in Generalized Chiral Perturbation Theory ∗
نویسنده
چکیده
The processes γγ → π0π0π0 and γγ → π+π−π0 are considered in Generalized Chiral Perturbation theory, in view of their potential sensitivity to the mechanism of spontaneous breaking of chiral symmetry and to various counterterms. The amplitudes are computed up to order O(p6). The event production rates are estimated for the Daphne φ–Factory and for a future τ–Charm Factory. ∗Work supported in part by TMR, EC–Contract No. ERBFMRX–CT980169
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تاریخ انتشار 1999