0 A two - pion exchange three - nucleon force based on a realistic πN interaction
نویسندگان
چکیده
The contribution of a ππ-exchange three-body force to the three-nucleon binding energy is calculated in terms of a πN amplitude. The latter is based on a meson-theoretical model of πN interaction developed by the Jülich group. Similar to a previous study based on simple phenomenological πN potentials a very small effect of the resulting three-body force is found. Possible origins of the two-orders-of-magnitude descrepancy between the present result and the values obtained for the Tucson-Melbourne three-body force are investigated. Evidence is provided that this discrepancy is most likely due to strikingly different off-shell properties of the πN amplitudes underlying the two approaches.
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