anti NN annihilation at low energies in a quark rearrangement model and decay widths of anti NN bound states

Using anti NN annihilation data at rest, we make a quark rearrangement model for annihilation into three mesons. This model describes the decay branching ratios of the anti pp and anti pn annihilations at rest satisfactorily. With this model we find considerable dependence of the annihilation on the isospin and spin of the initial anti NN system. By calculating the energy dependence due to the phase space of three mesons, we extend the model in the energy range E(c.m.) = 14OO MeV-2300 MeV where E(c.m.) is the total energy in the c.m.s. We find the strong energy dependence of the annihilation, with the annihilation probability below the anti NN threshold reduced drastically, compared to that at threshold. Based on the result for the quantum number and energy dependence, we discuss the possibility of the existence of anti NN bound states with narrow decay widths. (orig.)