Neutral-pion electroproduction on the proton near threshold.
نویسندگان
چکیده
The neutral pion electroproduction on the proton is considered in the framework phenomenological model based on the PCAC, current algebra with hard pions and chiral symmetry breaking interaction. The swave differential cross-section of the electroproduction of neutral pions off protons near the threshold is predicted as function photon momentum transfer squared k2 . The swave multipoles ReE0+ and ReL0+ as function of the energy of the π 0psystem are given for the small k2 and k2 = 0.1(GeV/c)2 . The results are compered with the experiment. It is shown the significant role of the explicit chiral symmetry breaking.
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ورودعنوان ژورنال:
- Physical review letters
دوره 74 18 شماره
صفحات -
تاریخ انتشار 1995